搜档网
当前位置:搜档网 › Odiset Online distributed session tracing using agents

Odiset Online distributed session tracing using agents

Odiset Online distributed session tracing using agents
Odiset Online distributed session tracing using agents

ODISET: On-line Distributed Session Tracing using Agents * Salvador Mandujano (smv@itesm.mx) Arturo Gal van (agalvan@itesm.mx)

Center for Intelligent Systems

Instituto Tecnologico y de Estudios Superiores de Monterrey

Monterrey, Mexico

Abstract

When a security incident occurs it is sometimes

necessary to identify its causes for legal and

cautionary purposes. In an attempt to hide the

origin of her connection, a malicious user may

have jumped from a source host h8 into a series

of hosts h1 € H = {h1,h2,..., h n} before breaking

into final target h t. This connection sequence

describes a path that makes it difficult to find h8

given h t due, in part, to the prohibitive amount of

cooperation and synchronization that is required

in practice by administrators. This paper describes

a distributed rule-based model that automates this

tracing process on-line with a 0(\H\)) worst case

scenario. Autonomous agents collaborate on the

tracing and detection of the origin of an interactive

connection using a loop unwinding technique and

incorporating public key cryptography to create

ciphered channels that allow them for secure com-

munication. To meet the challenges of minimum

system workload and improved robustness, the

prototype features lightweight design and imple-

mentation as well as a dynamic port-allocation

scheme to prevent sniffing and denial of service

attempts. We describe the proposed model and

present the experimental results obtained with the

prototype system ODISET.

1 Introduction

Unauthorized access to computer systems is increasing in parallel with the growth of the Internet (iRapalus, 2002]). For purposes of protection, accountability and liability, the need for connection back-tracing is a reality in the areas of cybernetic-law enforcement and computer security. The au-thentication structure of our networks as well as their dis-tributed nature complicates the task of spotting the host from *This project was supported by the INSYS Computer Security Research Grant (Cdtedra INSYS de lnvestigacidn en Seguridad In-formdtica) of Instituto Tecnol6gico y de Estudios Superiores de Monterrey which a connection sequence stems. If some sort of anoma-lous activity is observed from one of our users, it may be nec-essary to trace the origin of the session in order to identify the person behind it. In most cases, this is not easy to accomplish [Yoda and Etoh, 2001].

Within the domain of a L A N, it is rather straightforward to perform this tracing given that system administrators usually have access to all the hosts within their LAN. Unfortunately, not all sessions come from the inside. If a connection is re-ceived from the outside, we will have to contact the admin-istrator of a remote host h r in order to discover the identity of the user or the next link of the connection path or chain. Our fellow administrator will have to look into her system to realize that, perhaps, it has been compromised as well. It is possible that the user we arc looking for is using h r as a step-stone to reach our server. In that case, we will have to contact some more system administrators within the country and/or abroad [Cheswick and Bellovin, 1994] [Stoll, 1987]. This has obvious implications time and cost-wise.

Once a system has been compromised, the perpetrator may have left back-doors installed to facilitate future access to the system. Using interactive sessions, she may visit the system again even when the software has been patched and her back-door remains untouched. It is not necessary for the user to be logged on in order to be detected. Audit trail files can be used to do off-line tracing but this can be a tough task since audit logs may have been tampered with or deleted.

In the case of connections to web servers through HTTP and HTTPS, for instance, the hosts that compose the connec-tion chain between client and server cannot be easily modi-fied. Some components of the routing system would have to be modified in order to force the packets to follow a particular path. In the case of interactive sessions, however, applications such as t e l n e t, l o g i n, r l o g i n and s s h allow a user with suitable access permissions to connect from host to host back and forth creating loops at will to scramble her connec-tion path a little. This significantly complicates the structure of the chain and the amount of effort required to detect the root host h8 from where she is actually starting everything up. In fact, the complexity of back-tracing a connection across a set H of n hosts maybe small for a small n and a small num-ber of connection hops, but it rapidly increases as n becomes larger due to the number of hosts that a chain may contain.

One of the challenges of intrusion detection is to accu-

rately identify the main causes of an incident. The ultimate

goal is to catch intruders in real time and our objective is to help intrusion detection systems do the part of session trac-ing on-line. There are some intrusion detection and intrusion response tools [Yoda and Eton, 2001] [Asaka et a/., 1999] [Wang et al, 2001] that provide some sort of off-line con-nection tracing that also performs data correlation with previ-ously recorded user activity information.

This paper proposes an on-line approach that makes use of intelligent agents to identify the origin of a live session by unwinding connection loops. Instead of using historical au-dit trails, this model relies on evidence captured on operating system tables that are continuously refreshed by the system. For this reason, it is not likely that these tables experience changes that go unnoticed. The communication structure of the agents uses RSA public-key cryptography [Rivest et al, 1979] [Schneier, 2001] to implement an encryption model that protects all communications between agents. One of the main issues of the multi-agent approach to automatic secu-rity monitoring is the overhead imposed by this sort of tools [Weiss, 1999] [Spafford and Zamboni, 2000]. Our prototype system ODISET was built from a lightweight design that does not represent a performance threat, making it ideal for wide deployment through an open source operating system. We present the design ideas behind the model, the tracing and communication techniques, the loop-unwinding method, as well as some experimental results of the first release of the prototype.

The rest of this paper is organized as follows: Section 2 explains the problem of connection back-tracing. Section 3 discusses relevant related work in the area. Section 4 is a description of our solution approach and the implementation issues of the prototype. Section 5 includes experimental re-sults and findings. Conclusions and future work are in section 6 right before the listing of bibliography and references.

2 The Problem of Connection Back-tracing Given a set of hosts H = {h 1, h 2,..., h n ), with a user

could create a connection chain of m hops as follows: from

host h i into from into from into

and so on, until finally connecting to target host ' The

problem of connection back-tracing is: given the set H, the target host and username connected to find the hosts that compose the connection chain and identify its root host For a small this problem is straightforward. Just a

few hosts need to be analyzed in order to identify the source

of a connection sequence. However, as n becomes larger (e.g.

n 2), the complexity of the problem increases since a larger number of hosts in H multiplies the possibilities of cre-ating a more confusing connection path.

System administrators have limited access to information

on who is connecting to one of their servers. On a LAN, ad-ministrators typically have login access to all servers, which

makes the tracing process easier; however, for connections

coming from the outside of the LAN, they will be unable to

freely access all other servers for scrutiny. The visibility of

this type of connections reduces to one link of the connec-

tion chain. That is, an administrator can only see the terminal number or the IP address/host-name of the immediate host from where the users are logging on. She is unable to tell, however, whether that host is in fact h i (the machine from where the user is actually typing in commands). In order to find out whether that is the root host or not, she will have to contact the administrator of the remote system who, in turn, will have to perform a similar checking.

This job is cumbersome and requires time, communication, and trust from the parties involved. For the case of a connec-tion that has been closed already, audit information will have to be examined in order to find the nodes of the chain that lead to the origin of the connection. This off-line sort of tracing has an important flaw: it counts on the existence and integrity of audit log files. For clean systems this would not be a prob-lem but, for systems that have been compromised, and, in the case of a connection chain created to perpetrate an attack this could probably be the case, these files could have been tam-pered with during a previous break-in f Yoda and Etoh, 2001 ]. On the other hand, if a connection is still alive, i.e. there is a flow of packets between source and destination, information contained on system tables and network packets can be used to trace the user while she is on-line. That is, precisely, our approach.

3 Related Work

There are some projects that touch on the problem of con-nection route tracing. One of them is the method proposed in [Yoda and Etoh, 2001]. This model implements network traffic monitors that perform session tracing once a server has been compromised. A system that computes deviations from the traffic observed at two different hosts helps determine if these hosts were used in the same connection chain. Since checking network traffic at a node involves huge amounts of data, multiple packet monitors permanently filter and record specific system activity to build their own logs. These files

are analyzed by a data correlator to identify the hosts of a con-nection chain. It is important to notice that this system deals with the problem of deleted logs by creating its own records. These records, however, may be the target of the same type of attack. IDA (Intrusion Detection Agent system) [Asaka et al, 1999] is another system that detects the origin of an infor-mation exchange related to an incident. It is primarily an in-trusion detection system that employs mobile agents to detect

local attacks. From a main host, investigation agents are sent over to the requester that needs an integrity check. These agents use the MLSI (Marks Left by a S uspected Intruder) strategy to reduce the amount of data needed to flag system

activity as anomalous. In order to collect further information on a break-in, IDA does passive route tracing using audit log data. The structure of the tracing method is not specified by the authors but its agents broadcast connection evidence to their peers as a way of identifying possible hosts involved in the attack. The TBAIR system (Tracing-based Active Intrusion Re-sponse) [Wang et aL, 2001] is a network-based intrusion de-tection tool that, unlike most traditionally-passive intrusion

detection systems, adds active response to security events us-ing a technique called Based on Sleepy Watermark Tracing. TBA1R tries to attack the root of the vulnerability exploit-ing problem by locating the originators of the incident to hold them accountable for their intrusions and their method is based on the analysis of evidence collected from the net-work.

Thumbprinting [Staniford-Chen and Heberlein, 1995] is a technique that places several processes across the network in order to capture activity signatures or "thumbprints". This method does not require to have processes on all hosts and, like in the case of [Yoda and Etoh, 2001], it replicates packet information for future review. This system is based on the fact that the packet content of a session passing though a set of hosts is invariant and can be compared in order to identify a host in the chain. This system is capable of detecting the root of a connection but it is not designed to identify the exact hosts that are part of the chain.

The approach that we present here through the implemen-tation of the OD1SET system differs from these previous projects in the following manner. It performs on-line rather than off-line tracing (i.e., it does not use audit logs). The sys-tem does not incorporate agent mobility. Instead, it uses a distributed model using agents that communicate over secure channels for sharing information. Unlike some other models, ODISET is able to not only identify the origin of the con-nection but also all the hosts that are part of the connection

chain.

Figure 1: Basic composition of an ODISET tracing agent: public and private encryption keys, client functionality, server functionality, rule base, and knowledge base (connection chain tree + user data).

4 Solution Approach using Agents

"We require systems that decide for themselves what they need to do in order to satisfy their design objectives. Such computer systems are known as agents" [Weiss, 1999]. The use of agents for performing system assurance activities [Spafford and Zamboni, 2000] that typically require the skills of a human (e.g. inference, learning and decision mak-ing) makes possible the development of automatic or semi-automatic tools that aid system administrators in their task of securing a system.

The distributed nature of agents allows for more efficient, parallel data processing. We take advantage of this feature

MULTIAGENT SYSTEMS that perfectly fits into a network environment [Huhns and Singh, 1998] in order to speed up connection back-tracing using autonomous agents. This approach eliminates the need for centralized data collection and analysis, a method that is still in use and that represents a design deficiency by putting the availability of a system in risk (monolithic systems typi-cally suffer from having a single-point-of-attack).

In order to provide the agents with survivability features that make them more resistant to attack, each agent owns a digital certificate to create private communication channels when interacting with its peers. With the intention of reduc-ing the probability of Denial of Service (DoS) attacks targeted toward the agents, a port-allocation scheme is used. This scheme dynamically changes the socket port numbers used by the agents in order to avoid being monitored or receiving unfinished-protocol requests.

This system features rule-based agent behavior through which individual agents are capable of detecting connection loops in a chain. The approach deals with the problem of deleted or damaged audit information by not using historical audit data. Agents look up information on dynamic session tables in order to extract data relevant to the tracing process. The process table, for instance, is not easily modifiable as au-dit logs are. The system might go down due to inconsistency if changes are made to this type of file, which would make the change evident.

4.1 Proposed Model

Tracing method and security

The system is composed of a number of tracing agents (Fig-ure 1) that communicate with each other sharing information on user connections. There is an agent running at each host h i and the ideal situation is having an agent running on every host of the network. Every agent has client and server capa-bilities that enable it to request information from other agents and to supply information to them. An agent is not useful by itself, it needs to collect information from the others in order to identify the links of a connection chain. The agent at the target host will eventually collect information from a number of its peers and will inform to the local administrator about the origin of the connection.

The perceptions of a tracing agent are received from two main sources: 1) the state of the system regarding user ses-sions and connections, and 2) messages from other agents re-questing or providing information.

The environment an agent inhabits is highly dynamic and provides the communication channel necessary for an agent to stay in touch with its peers over the network. This envi-ronment can also represent a threat to the tracing system if malicious users gain access to it.

As a result of the changes perceived by an agent, it can perform a number of different actions: a) send messages to an agent, b) request messages from an agent, c) broadcast messages to all agents, d) generate encryption keys, e) en-crypt messages, f) decrypt messages, g) identify connection loops, h) retrieve system status information, and h) save its knowledge to a safe location.

The knowledge of an agent is stored on a repository known

751

as knowledge base (KB). This KB includes tracing host infor-mation and user data. A tree structure stores the information on the hosts that are part of a connection chain. Information regarding user names, login times and dates is stored on a sep-arate structure. These two elements represent all the knowl-edge an agent has about the state of its environment. Should this knowledge be lost, the agent would lose track of previous events and would have to be updated by its peers.

The actions an agent takes depend on the information of the state of the system and its perceptions [Russell and Norvig, 1995]. Embodied into the agent are a set of rules that enable the agent to work autonomously deciding what to do. As new knowledge is fed into the KB more rules from the rule base need to be analyzed before making any conclusion and pro-ceeding (the rule base is composed of 23 rules). The type of perceptions and actions do not change but the state of the environment does evolve hereby modifying the behavior of agents. The type of rules that make up the rule base are of the form:

R1:

IF ((HOW-CONNECTED(User)^Console) AND

(W H A T-D O I N G(U s e r)=S s h-t o(T a r g e t))

)

TRACTNG-DONEO;

R2:

TF ( (MESSAGE-TYPE (Messa ge) t r ac i n g-r e q u e s t) AND (VALID-PUBLIC-KEY(P-

k e y)=F a l s e)

)

DENY-CONNECTIONO AND BROADCAST-

TREE () AND ALERT() ;

In order to protect their information exchanges, all agents have an RSA key-pair that is used to negotiate symmetric ses-sion keys before encrypting their messages. Encryption at this level guarantees that the information will not be visible at any point before reaching the top of the IP stack of the recipient party. This will deter sniffing attacks that arc other-wise possible on plain text agent communications [Jansen et al., 2000].

The tracing process starts when a connection needs to be monitored. Agents at target host h t receives local informa-tion from the system and checks for remote connections. If there is a connection from a remote machine h r, A will con-tact agent B at host h r in order to research the connection. For this purpose, a private channel will be opened using the asymmetric encryption keys of the agents. A symmetric ses-sion key will be agreed upon and all messages will be en-crypted with it for that exchange. The same procedure will be followed if there are relevant connections from outside of the host of h r coming into the server. A set of secure channels will be setup by the agents in order to share the information they have regarding connections and user activity. One hop at a time, the links composing a connection chain will be found.

The tracing information obtained by an agent is shared with the rest of the agents through broadcast communication (i.e., an agent sends a message to all existing agents). This guaran-tees that the KB's of the agents are consistent with the state of the environment and that, in the event of a security incident, the knowledge acquired by an agent will not be lost as it has been replicated and enriched by other agents.

Figure 2: Loop unwinding. If a user connects from host h8 into host h t doing a loop through hops 1, 2, 3, 4, 5 and 6 as shown above, agent A at h t will start the tracing process and will be able to identify the loop to reduce tracing time in the future.

If we have a set H of n hosts, and a user creates a connec-tion chain C of m hops, the system will behave well with a O(n) worst case scenario. Suppose m n. If the number q (0 q m) of connections that go from host h x into host h y - or vice versa - form a loop, the arrangement of the agents will find at most two relevant connections between the hosts hereby unwinding the loop. This is due to the fact that an agent is capable of identifying repeated connections toward itself by storing information on what users are connected. For the case of loops passing through k hosts, the chain will be re-duced to at most 2k hops. This makes a worst case scenario of O(n) with n =

Several methods exist (see [Wolf and Lam, 2000] for a ref-erence) for loop unwinding, mostly in the compilers and dis-crete mathematics areas. In our model, we utilize a simple technique based on observed activity. An agent first stores user name and host-name information on its KB. When a trac-ing process is started, an agent will engage in communication with several neighbor agents in order to collect data that al-low them to draw conclusions. Each time agent A receives new information, it checks its KB for loops. This is done as follows (see Figure 2). All tracing requests have an ID num-ber w. Agent A initiates a tracing round. If while waiting for news on a particular w the agent is being asked by a coop-erating agent B for information to complete tracing round w as well, the agent knows it is part of a loop since it is receiv-ing information on a tracing round that it started (all agents, including initiators have this property). The trace is stored on its KB tree T and, if the user being traced repeats a loop that passes through the same host where agent A is located, this agent will reduce the tracing time by omitting a further requests to follow a loop.

Dynamic port-allocation protocol

Network service daemons usually work on a particular port listening for requests. Port-scan attacks try to reveal what are the services listening on the ports of a host. Once this is done, they look for vulnerabilities present on one of those services and, if they find one, they are in a position to exploit such a

flaw on the port they have previously identified. DoS attacks are started with port-scans to send a large number of request for service to a vulnerable port so that, at the end, there are so many requests pending to be answered - usually incomplete requests at protocol level - that the machine slows down and needs to be restarted. Additionally, if the service on that port does not support encryption, the traffic going through it may be observed by a network sniffer. All network services using sockets on a port may suffer from this sort of attacks. We propose a model to minimize the likelihood of being a target. As we mentioned, all com-munications between agents is encrypted, so sniffing of plain text is impossible in practice. In order to deter attacks at the service port, we propose a technique that can be used in real life with radio equipment: channel switching (this is currently being implemented on the prototype). Initially, all agents lis-ten on a well-know port p. The requests for service on that port do not allocate significant system resources according to the implementation. This basic port is used just to agree on the actual communication port q for the exchange (q p). For this, the receiver proposes a valid port number that is sent to the other party over a secure channel. They imme-diately switch to that port for exchanging information. This

port switching is repeated during the session within a fixed

short period of time. In order to defeat this protection mecha-nism, a port scan will have to be run again and, by the time it succeeds, the communication may have moved to a different port. Frequency of switching and encryption this mechanism possible. 4.2 Implementation of the Model As a proof of concept, the model was implemented on a pro-totype system named ODIS ET (On-line Distributed SEssion

Tracing). Every agent is a stand-alone process implemented

with sockets for providing client and server functionality. It can request information from others and it can share infor-mation as well. A 1024-bit RSA key-pair {Kp ub ,K priv } is generated before the agent is launched. Once the agent is

started up, it is ready to collaborate in the tracing of a ses-sion. When contacting a peer agent, it exchanges public keys

and verifies the signature on the received key. The certifica-tion must come from the ODISET master key whose public-key is accessible to all agents. In order to speed up message

encryption, and given that encryption with public-key meth-ods is much slower than the one using private-key algorithms

[Schneier, 2001 ], the agent that is to send a message does the

following: 1) it generates a session key K DE S for symmetric

encryption, 2) it then encrypts the message M using KDES * 3) it encrypts KDES using the public key of the recipient, and, finally, 4) it sends the encrypted session key and the en-crypted message to their destination. The implementation of the RSA and DES algorithms is based on version 2.0 of the RSAREF?cryptographic library by RSA Laboratories. The first release of the ODISET prototype was developed

on a RedHat Linux 8.0 box. Although agent templates can

be easily obtained from multiple agent-generator systems and

for different compilers and interpreters, they typically put un-necessary functionality into the agent that produces heavy

agents. For this reason, and with the intention of providing

the best performance possible, the implementation was made in C by minimizing the number of libraries to include. Con-sidering that programs and data files may be damaged after a security incident and that a security tool can not rely on them, our agents do not use the output of programs such as w, who and ps to read system tables like utmp and wtmp. They incorporate this functionality into its own body, which gives them extended independence. The size of each agent is around 20 Kbytes to which we add two encryption keys

that need to be uploaded at certain point (around 4 additional

Kbytes) as well as the knowledge and rule bases that are never

uploaded entirely into memory. The knowledge base of each agent includes a tree structure T where all connection chains are stored. Whenever a host has received all the information regarding a particular session, it stores the connection chain c = [h i h 2 ... h ri ] into

T and sends it to all available agents. Every agent reads c and finds the hosts in c that match its own tree. It then creates new branches to keep its KB up-to-date. The rule base is encoded along with the body of the agent. Being an static structure, it is not necessary to keep it as a separate entity. 5 Experimental Results In order to evaluate the efficiency of the method, multiple ex-periments were prepared. After some implementation cor-rections, all of them were successful after the unwinding technique was incorporated. The testing facility is a set of seven Linux machines running kernels 2.1 and above on Red-hat 7.2, RedHat 7.3, RedHat 8.0 and Mandrake 8.0 operat-ing system installations. The general structure of the ex-periments consists of creating connection chains of length m {2,4,8,16,32} using n hosts where n {3,5, 7}. This maximum number of machines was selected since our experience tells it is highly improbable that, for session per-formance purposes, an attacker uses much more step-stone hosts. All cases where there is no loop in the chain, that is, where m = n are easily resolved so we prepared con-nections that include a series of loops along the chain. For instance, in the three-server setup, the connection goes in cir-cles from host hi into h 2< from host h 2 into host h 3, from host h 3 back into host h 3 and so on for a total number of m hops. The experiments show that the algorithm effectively unwinds the loops. When an agent finds the same loop repeated sev-eral times, it will not try to solve it over and over again. Its KB contains user and connection information that allows it to conclude that a user is creating a loop. Part of the contribution of this method is the fact that by using loop unwinding, the performance of the algorithm has an upper threshold that is, at most, linear on the number of

hosts n through which the user connects. A set of n agents will be in charge of tracing the connection and even for a very long chain, an agent located on each hosts guarantees

that loops will not delay the tracing process in any way. Table 1 includes tracing numbers with and without encryp-tion. Both columns indicate that the growth of the tracing time is below linear time with respect to the number of hops m (this makes us think this model should escalate well to large networks). The time difference from tracing with and without

Table 1: Tracing time with and without encryption (RSA key exchange + DES chaining block ciphering) with seven hosts (/i=7); m corresponds to the number of connection hops. encryption is significant. This only reminds us of the perfor-mance cost of using cryptographic algorithms to protect our data. It is not likely that a connection chain extends over more than thirty hosts, for instance. It follows that, even with 1024-bit keys, the use of encrypted communication is the way to go regarding agent communication for this problem.

The strengths of this model are its unwinding algorithm, the possibility of performing on-line tracing and the structure of an autonomous lightweight agent. The proposed dynamic port-allocation method can effectively deter communication sniffing and promises to be effective for the case of agent-based applications as well. A disadvantage of the system is that it works exclusively with alive connections. If, for one reason, the user disconnects the session from our host, the agents will go blind and will not be able to trace the in-truder. The model, however, can be easily extended toward off-line tracing, but there are already other systems, like the ones highlighted in Section 3, that cover that case. Another improvement area is the fact that an agent will see only users that are connected to a host through an interactive session us-ing commands that update system tables. If an intruder ex-ploits a vulnerability and gets to spawn a shell session at the host without having to run a remote connection command, she will not be seen. That is because these connection com-mands like r l o g i n and ssh write system activity informa-tion to system tables. If none of this programs is used by an intruder, the host will not record her presence and she will be able to go unnoticed.

6 Conclusions and Future Work

This model proves the feasibility of performing on-line con-nection back-tracing using lightweight autonomous agents in a distributed fashion. It also proposes two security mech-anisms that can be implemented on other software agents to make their communication structure more robust (these mechanisms are random port-switching and encrypted agent communication using certificates). We conclude that the adoption of a tracing system like this by multiple operating systems through a sort of agent sand box per host would in-deed contribute to solve security incidents more rapidly.

Future work includes a) the integration of the ODISET tracing tool into an agent-based intrusion detection system, b) the development of survivability methods for agents using replication, mobility and zero-loss mechanisms, and c) the extension of the tracing space to include dial-up connections. References

[Asaka et al, 1999] M. Asaka, M. Tsuchiya, T. Onabuta, S. Okasawa, and S. Goto. Local attack detection and intru-

sion route tracing. IE1CE Trans. Commun. New Paradigms

in Network Management, E82-B(l 1), November 1999. iCheswick and Bellovin, 1994] W.R. Cheswick and S.M.

Bellovin. Firewalls and Internet S ecurity: Repelling the Wily Hacker. Addison Wesley, 1994.

[Huhns and Singh, 1998] M.N. Huhns and M.P. Singh.

Agents and multiagent systems: Themes, approaches, and challenges. Readings in Agents, pages 1-23, Morgan Kaufmann, San Francisco, CA 1998.

[Jansen etal, 2000] W. Jansen, P. Mell, T. Karygiannis, and

D. Marks. Mobile agents in intrusion detection and re-

sponse. June 2000.

[Rapalus, 2002] P. Rapalus. Computer security survey 2002.

Technical Report 1, Computer Security Institute, CSI, and the Federal Business of Investigations, FBI, April 2002. [Rivest et al, 1979] R.L. Rivest, A. Shjamir, and L.M. Adle-man. On digital signatures and public key cryptosystems.

MIT Laboratory for Computer S cience, (MIT/LCS/TR-

212, technical report), January 1979.

[Russell and Norvig, 1995] P. Russell and E. Norvig. Arti-

ficial Intelligence: A Modern Approach. Prentice Hall, Englewood Cliffs, New Jersey, 1995.

LSchneier, 2001] B. Schneier. Managed security monitoring: Network security for the 21st century. Computer Security

Journal, 77.2,2001.

[Spafford and Zamboni, 2000] E. H. Spafford and D. Zam-boni. Intrusion detection using autonomous agents. Com-

puter Networks, 34:547-570,2000.

[Staniford-Chen and Heberlein, 1995] S. Staniford-Chen and L.T. Heberlein. Holding intruders accountable on the internet. IEEE Symposium on Security and Privacy, 1995. [Stoll, 1987] C. Stoll. The Cukoo's Egg. Double Day, 1987. iWang era/., 2001] X. Wang, D. Reeves, and S. Wu.

Tracing-based intrusion response. Journal of Information

Warfare, 1(1), September 2001.

[Weiss, 1999] G. Weiss. Multiagent S ystems: A modern Introduction to Distributed Artificial Intelligence. MIT Press, 1999.

[Wolf and Lam, 2000] M.E. Wolf and M.S. Lam. A loop transformation theory and an algorithm to maximize par-

allelism, volume 2, pages 452-471, October 2000.

[Yoda and Etoh, 2001 ] K. Yoda and H. Etoh. Finding a con-nection chain for tracing intruders. 6th European Sympo-

sium on Research in Computer Security (ESORICS 2000), pp. 191-205, October 2001.

坚定不移贯彻新发展理念

第十讲坚定不移贯彻新发展理念 党的十八大以来,习近平总书记顺应时代和实践发展的新要求,坚持以人民为中心的发展思想,鲜明提出要坚定不移贯彻创新、协调、绿色、开放、共享的新发展理念,引领我国发展全局发生历史性变革。新发展理念集中体现了我们党对新的发展阶段基本特征的深刻洞察和科学把握,标志着我们党对经济社会发展规律的认识达到了新的高度,是我国经济社会发展必须长期坚持的重要遵循。 一、引领我国发展全局深刻变革的科学指引 创新、协调、绿色、开放、共享的新发展理念不是凭空得来的,而是在深刻总结国内外发展经验教训、分析国内外发展大势的基础上形成的,也是针对我国发展中的突出矛盾和问题提出来的。新发展理念深刻揭示了实现更高质量、更有效率、更加公平、更可持续发展的必由之路,是引领我国发展全局深刻变革的科学指引,对于进一步转变发展方式、优化经济结构、转换增长动力,推动我国经济实现高质量发展具有重大指导意义。 新发展理念是针对我国经济发展进入新常态、世界经济复苏乏力形势提出的治本之策。党的十八大以来,面对极其错综复杂的国内外经济形势,以习近平同志为核心的党中央审时度势,从我国经济发展的阶段性特征出发,作出我国经济发展进入新常态的战略判断。世界经济在大调整大变革之中也出现了一些新的变化趋势,2008年国际金融危机深层次影响持续蔓延,西方国家结束黄金增长期,世界经济进入深度调整期,国际贸易低迷,金融市场跌宕起伏,保护主义明显抬头。面对这种新变化新情况,再沿袭粗放发展模式、简单地追求增长速度,显然行不通,必须确立新发展理念来引领和推动我国经济从高速增长阶段转向高质量发展阶段,不断开创经济发展新局面。 新发展理念是针对当前我国发展面临的突出问题和挑战提出的战略指引。我国物质基础雄厚、人力资本丰富、市场空间广阔、发展潜力巨大,经济发展方式加快转变,新的增长动力正在孕育形成,经济长期向好基本面没有改变。同时,发展不平衡不充分的一些突出问题尚未解决,发展质量和效益还不高,创新能力不够强,实体经济水平有待提高,生态环境保护任重道远;民生领域还有不少短板,脱贫攻坚任务艰巨,城乡区域发展和收入分配差距依然较大,群众在就业、教育、医疗、居住、养老等方面面临不少难题;等等。这些问题,必须着力加以解决。新发展理念就是针对这些问题提出的。创新发展注重解决发展动力问题,

深入理解ServletJSP之Cookie和Session原理

由于H T T P协议的无状态特征,W e b应用中经常使用C o o k i e和S e s s i o n来保存用户在与系统交互过程中的状态数据。下面通过分析H T T P协议对C o o k i e和S e s s i o n的工作原理加以了解。 一、C o o k i e C o o k i e的含义是“服务器送给浏览器的甜点”,即服务器在响应请求时可以将一些数据以“键-值”对的形式通过响应信息保存在客户端。当浏览器再次访问相同的应用时,会将原先的C o o k i e通过请求信息带到服务器端。 下面的S e r v l e t展示了C o o k i e的功能。 ......... p u b l i c v o i d d o G e t(H t t p S e r v l e t R e q u e s t r e q u e s t,H t t p S e r v l e t R e s p o n s e r e s p o n s e) t h r o w s S e r v l e t E x c e p t i o n,I O E x c e p t i o n{ r e s p o n s e.s e t C o n t e n t T y p e("t e x t/h t m l"); P r i n t W r i t e r o u t=r e s p o n s e.g e t W r i t e r(); S t r i n g o p t i o n=r e q u e s t.g e t P a r a m e t e r("o p t i o n"); i f("s h o w".e q u a l s(o p t i o n)){ //获得请求信息中的C o o k i e数据 C o o k i e[]c o o k i e s=r e q u e s t.g e t C o o k i e s(); i f(c o o k i e s!=n u l l){ //找出名称(键)为“c o o l”的C o o k i e f o r(i n t i=0;i"+c o o k i e s[i].g e t N a m e()+":" +c o o k i e s[i].g e t V a l u e()+""); } } } }e l s e i f("a d d".e q u a l s(o p t i o n)){ //创建C o o k i e对象 C o o k i e c o o k i e=n e w C o o k i e("c o o l","y e a h!"); //设置生命周期以秒为单位 c o o k i e.s e t M a x A g e(20); //添加C o o k i e r e s p o n s e.a d d C o o k i e(c o o k i e); }

管理学原理

管理学原理 管理学是一门综合性的交叉学科,是系统研究管理活动的基本规律和一般方法的科学。管理学是适应现代社会化大生产的需要产生的,它的目的是:研究在现有的条件下,如何通过合理的组织和配置人、财、物等因素,提高生产力的水平。 管理是指在特定的环境下,管理者通过执行计划、组织、领导、控制等职能,整合组织的各项资源,实现组织既定目标的活动过程。 它有三层含义: (1) 管理是一种有意识,有目的的活动,它服务并服从于组织目标。 (2)管理是一个连续进行的活动过程,实现组织目标的过程,就是管理者执行计划组织领导控制等职能的过程。由于这一系列职能之间是相互关联的,从而使得管理过程体现为一个连续进行的活动过程。 (3)管理活动是在一定的环境中进行的,在开放的条件下,任何组织都处于千变万化的环境之中,复杂的环境成为决定组织生存与发展的重要因素。 折叠相关书籍 目前还没有一套普遍公认的完整的管理学原理体系。不同版本的管理学教科书和辞书,各有一套不同的管理学原理体系。 折叠《现代管理科学词库》

朱新民、李永春、周吉主编《现代管理科学词库》(上海交通大学出版社1986年9月) 中提出了下列管理原理体系:《现代管理科学词库》 ⑴系统原理:为了达到最佳管理,必须进行系统分析,抓住系统的三个环节:目的性、全局性、层次性。 ⑵整分合原理:现代高效率的管理,必须在整体规划下明确分工,在分工基础上有效地综合。 ⑶反馈原理:面对不断变化的客观实际,必须做到灵敏、准确、有力的反馈。 ⑷封闭原理:任一系统内的管理手段必须构成一个连续封闭的回路。 ⑸能级原理:将不同的个人,根据其能力大小,分别安排在适当层次的组织机构中,做到人尽其才,能者多劳。 ⑹弹性原理:管理必须保持充分的弹性,以适应各种可能的变化,实现动态管理。 ⑺动力原理:管理必须有强大的动力,包括物质动力、精神动力,信息动力,才能持续有效地进行。 折叠《管理学》 张正河、陆娟主编《管理学》的原理体系为: ⑴人本原理:以人(员工)为中心,以人为本。

周三多《管理学》简介

周三多版《管理学》 周三多版《管理学》是教育部“面向世纪教学内容和课程体系改革计划”以及高等教育出版社“高等教育百门精品课程教材建设计划”的研究成果, 是国内最受欢迎的标准管理学教材之一,并被全国余所高等院校广泛采用并作为管理学教学及研究生入学考试、博士生入学考试的典范教材。 周三多版《管理学》章节目录编排包括按照管理职能划分的总论、决策与计划、组织、领导、控制、创新等六个内容部分,分为十八章。文都网校考研《管理学》在授课过程中,教师会依次深入剖析专业课核心知识点对应的复习资料、基础知识框架梳理及其解析内容等。目的是帮助学生发现题目设置和解答的规律性,掌握题目对应的知识点和熟悉解题的金钥匙。从而降低考研专业课的复习难度,迅速提高专业课知识水平,为下一阶段的学习做好储备与铺垫。 考试重点难点早知道: 一、德尔菲法的特点;法约尔的跳板原则;切斯特.巴纳德对组织理论的贡献;管理的理念和方法对管理过程和结果的影响;管理的效率和效果的区别;社会人假设;管理科学理论。 二、终极性价值观与工具性价值观;管理者的责任;管理伦理;:跨文化管理;组织外部环境。 三、组织中的信息管理工作;信息系统;与Ⅱ;;虚拟团队;非确定性决策;群体决策;程序和非程序决策。 四、计划;计划与决策的关系;“计划跟不上变化,所以制定计划没有意义”如何理解这句话;在企业中怎样进行计划管理。 五、战略计划;分析法;企业战略;计划审评技术;企业目标与企业的宗旨和使命的关系;目标管理利弊;有效推行目标管理的条件。 六、委员会;有机式组织;直线人员与参谋人员;矩阵组织结构;虚拟组织;组织扁平化;授权;组织“横向化”;非正式组织;管理幅度与管理层次。 七、素质模型;弹性福利计划;组织氛围;雇员援助计划;纯基薪计划;评价中心;周边绩效;薪酬水平;劳动关系;团队管理;人力资源管理与人事管理;人本管理;薪酬管理的外部公平、内部公平与员工公平;培训效果评估;员工福利;培训需求分析;工作分析。 八、建设性冲突;组织层面变革;减少破坏冲突的方法;对建设有中国特色的组织文化的看法;企业文化。 九、变革型领导;概念技能;领导与管理;领导应该具备的技能;权力在行使领导职能的作用。

管理学原理

管理学原理(第二版)2012年4月考试考前练习题 一、单选题 1.在现实中我们经常能够看到这样一种现象:一所高校的校长往往是在某学科造诣很高的学术专家,一所医院的院医学专家。但是,有些学术专家家却未能成为称理者。针对上述象,正确的评价是(D )。 A.就管理层次而言,技能重要B.搞技术的人往往不善于与弱,难以担当管理之职C.对高层管理者来念技不重要D.就管理层次而言,越往上概念技能越重要,越往下技术技能越重要 2.对组织内外部条件各方面内容进行综合和概括,进而分析和威胁的环境分析方法是指( A )。 A.SWOT分析B.PEST分析C.行业竞争结构分析D.波士顿矩阵分析 3.某公司总经理除了直接指挥几个地区分公司经理之外,他还设立了人事助理、财务顾问、公共关系顾问等职,并配备了相应的人顾问授予了直权限。这个过程反映了哪两种职权之间的转换?(D ) A.从职能职权到直线职权B.从职能职权到参谋职权C.从参谋职权到直线职权 D.从参谋职权到职能职权 4.某企业有较强的产品研究开发和市场营销能力,能够在产品设计、工艺技术和营销上不断发挥创造性;在产品质量、技术以及营销和服务等方面有着良好声誉。该企业适宜采用的竞争战略是(B )。 A.低成本战略B.差异化战略C.重点化战略D.集中化战略5.车间主任老王最近发现,质检员小林一有空就与机关的小刘、设计室老张和门卫老杨等一起谈足球,个个眉飞色舞,而参加例会却经常没精打采。对此,车间主任老王最好采取什么措施?(C ) A.批评小林,并对他提出要求,以后不许在厂里和他人谈足球B.严格执行车间工作制度,对擅自违反规定者加以严厉惩罚C.在强调必须遵守工作制度的同时,在车间搞一个球迷协会,并亲自参加协会活动D.对上述情况不闻不问,任其自由发展 6.在组织绩效管理中,核心环节是( C )。 A.绩效设计B.绩效改进C.绩效评估D.绩效反馈 7.某公司为了扭转销售不力的局面,提升销售能手张先生出任销售部经理。到了年末,销售部业绩虽然较上一年略有下降,但张经理一人完成的订单占部门完成任务总量的53%。在如何评价张经理的工作一致。下述哪种评价最恰当?( D ) A."能抓住耗子的猫就是好猫"。张经理个人能予大力表彰 B.产品的销售客观上依赖张经理的努力他特别奖励 C.对张经理的奖惩应该依据部门部门目标,所以必须对张经理予以严惩D.张先生是一个优秀的销售人员,但不是一个合格的经理人员。公司需要尽可能在不影响其积极性的基础上重新调整其工作 8.《孙子兵法》是一部不朽的军事著作,时至今日,对企业经营战略仍有重要指导作用。孙子认为:作战的势态的。他指出“故兵无常势,水,谓之神”。从管理角度看,这一描述更符合( C )。 A.权责对等原则B.系统理论原则C.权变理论原则D.统一指挥原则 9.某公司随着经营规模的扩大,由王副总经理直管的营销队伍人数也从3人增加到近100人。最近,公司发现营,但又找不到确切的原因。从管理的角度看,出现这种情况的主要原因是(C )。 A.营销人员太多,产生了鱼龙混杂的情况 B.副总经理投入管理的时间不够,致使营销人员产生了看法 C.副总经理的管理幅度太宽,以至于无法对营销队伍实行有效的管理 D.营销队伍的管理层次太多,使得副总经理无法与营销人员实现有效的沟通10.风险型决策与不确定型决策的区别主要在于( D )。 A.风险型决策承担的风险相对于不确定型决策来说要小 B.风险型决策面临的是多种可能的自然状态,而非确定型决策面临的是无法预知的自然状态 C.二者的区别不明显 D.风险型决策可以预测未来自然状态出现的概率,而非确定型决策不能预测概率 11.目标管理的基本过程为(B )。 A.奖励和开始新的目标循环—建立目标体系—检查和评价—组织实施 B.建立目标体系—组织实施—检查和评价—奖励和开始新的目标循环 C.检查和评价—奖励和开始新的目标—建立目标体系—组织实施 D.奖励和开始新的目标循环—建立目标体系—组织实施—检查和评价12.在以下几项管理业务中,哪一项该由公司总经理亲自处理和拍板?(C )A.关于公司各部门办公电脑的分配方案B.对一位客户投诉的例行处理C.对一家主要竞争对手突然大幅降价做出反应D.对一位公司违纪员工按规章进行处理 13.在管理决策中,许多管理人员认为只要选取满意的方案即可,而无须刻意追求最优的方案。对于这种观点,以下哪种解释最有说服力?( D )A.现实中不存在所谓的最优方案,所以选中的都只是满意方案 B.现实管理决策中常常由于时间太紧而来不及寻找最优方案 C.由于管理者对什么是最优决策无法达成共识,只有退而求其次 D.刻意追求最优方案,常常会由于代价太高而最终得不偿失 14.刚进公司的几个大学生很自然地形成了一个团队,大家兄弟相待,一起解决各自遇到的难题,包括各自负责的经营工作。几年下来,这个团队的凝聚力很强,每个人都非常珍视这个团队。又过了几年,这个团队的成员普遍得到较好的发展,但地位、收入等方面并没有形成多大的差距,然而大家却都感到团队的凝聚力没有以前那么强大了。造成这个团队松散的原因是什么?(B )A.团队成员的能力增强了,独立性提高了B.没有更高层次的目标推动C.团队成员之间因工作繁忙而沟通太少D.没有及时吸收新的团队成员 15.曹雪芹虽食不果腹,仍然坚持《红楼梦》的创作,是出于其(C )。 A.自尊需要B.情感需要C.自我实现的需要D.以上都不是 二、多选题 1.组织结构的内容主要包括(BCDE)。 A.计划结构B.职能结构C.层次结构D.部门结构 E.职权结构 2.法约尔首先对企业管理职能做了科学的概括,他认为企业管理职能包括(ABCDE)。 A.计划B.组织C.指挥D.协调 E.控制 3.组织常用的控制手段有(ABCD )。 A.计划控制B.时间控制C.数量控制D.质量控制 E.政策控制 4.学习型组织强调的修炼内容有(ABCE)。 A.不断地追求自我超越B.善于改善心智模式C.善于为组织建立共同愿景 D.彻底改造流程E.善于学会系统思考 5.常见的部门划分方法有(ABCDE)。 A.职能部门化B.产品部门化C.地区部门化D.服务对象部门化E.工艺过程部门化 6.团队精神包含的内容有(ABC )。 A.团队凝聚力B.团队合作意识C.团队士气D.团队组织E.团队领导 三、判断题 1.利用波士顿矩阵分析方法,当产品的市场增长上应投入必要的资金,力求提高自己的市场份额。错 2.从赫兹伯格的双因素理论看,组织的政策员之报酬、工作环境等因素属于激励因素。错 3.信息沟通必须具备的要素有三个:发送者、接收者、所传递的内容。错 4.体现了“集中政策,分散经营”原则的组织结构形式是事业部制组织。对 5.平衡计分卡法最突出的特点是:将组织的远景、使命和发展战略与组织的绩效评价系统联系起来,它把组织的使命和战略转变展战略有明确认识,以实现战略和绩效的有机结合。对 6.管理者应具备的技能被划分为三类:技术技能、人际技能和概念技能。就管理层次而言,越往上人际技能越重要,越往下概念技能越重要。错 7.非程序性决策,是指对经常出现的重复性问题,并生产作本控制、对员工奖惩的实施等。错 8.横向一体化战略是指从产品的供、产、销等一系列相关业现有经营业务和规模的发展战略。错 9.组织的一般环境因素是指对组织目标的实现有直接影响的外部环境因素,一般包括资源供应者、竞争者、服务对象、政府管理部门及社会上的各种利益代表组织。错 10.企业的社会责任就是使利润最大化。错 11.马克斯·韦伯对管理理论的突出贡献是:从理论上把管理科学提到一个新的高度。错 12.有的观点认为组织应该鼓励冲突,认为冲突不突对于组织有效运作是绝对必要的。对

管理学原理实习报告

经济与管理学院 《管理学原理》实习报告 系别 专业班级 学生姓名 学号 实习报告题目参观海马汽车有限公司报告 实习课程名称管理学原理 课程实习形式参观学习 课程实习时间2009年12月31日 课程实习地点海马汽车有限公司 指导教师 二ΟΟ九年一月三日

实习目的:了解现代先进生产技术,开拓视野,领略现代企业管理模式,体会《管理学原理》所授课程的实践内涵 实习内容: 1、海马汽车公司整体简介,了解汽车企业文化 2、参观汽车总装车间,通晓汽车生产装配流程 3、观看跑道试车,体验汽车质量和风采 单位调查: 一汽海南汽车有限公司(FHC)位于海南省海口市,是以1988年购进的美国福特汽车公司菲律宾冲压厂和装配厂的全套设备为基础,引进美国、英国、日本的自动焊装及涂装等工艺生产线,建设而成的国有大型企业。经过十余年的发展,已拥有技术先进的冲压、焊装、涂装、总装汽车工艺生产线,机械加工、动力、理化试验、全自动综合立体仓库等辅助生产设施,和计算机管理系统,计算机辅助设计、制造系统,成为国家轻型客车与轿车的整车定点生产基地。年设计生产能力为整车5万辆。1992年,公司与日本马自达汽车公司(MC)合资成立海南马自达汽车冲压有限公司,引进开发323轿车、海马旅行车、面包车和MPV 系列车型,树立起高品质的海南马自达品牌。集团化发展是增强企业竞争力、实现产业结构调整的必经之路,公司于1998年1月18日进入一汽集团,轿车、MPV等产品纳入了集团和国家汽车产业统一规划。 海南马自达销售有限公司成立于1996年,注册资本1000万元。总经销海南马自达系列产品。公司在北京、上海、广州和成都设立了4个区域办事机构和一个车辆中转储运中心,在全国几十座大中城市都建立起集整车销售、配件供应、售后服务、信息反馈四位一体的海南马自达销售服务店,形成了全国性销售服务网络。公司率先推出“保姆式”服务方案,以顾客和产品为核心,梳理从市场调研、产品定位、运输保养、现场销售到售后服务全过程,创新人性化、制度化、精细化的市场销售与服务方式。 参观实习过程:

管理学课程简介

管理学课程简介(一) 1 管理学研究的四大职能不包括()。 A、计划 B、组织 C、控制 D、反馈 正确答案:D 2 德鲁克的管理学思想是以()为导向的。 A、目标 B、过程 C、控制 D、综合 正确答案:A 3 应用型管理学的内容有管理学历史、管理学流派、管理学前沿。()正确答案:× 管理学课程简介(二) 1 管理学所要培养的四个能力不包括()。 A、科研能力 B、应用能力 C、阅读能力 D、沟通能力

正确答案:C 2 问题导向的课堂中以()为主体。 A、教师 B、教材 C、教具 D、学生 正确答案:D 3 下面哪一项不是导向性课程的课程要求()。 A、个人意见 B、课前预习 C、课堂参与 D、多项沟通 正确答案:A 4 问题导向的课堂讨论重点在于逻辑分析。() 正确答案:√ 5 普华永道变革整合小组编著的《管理悖论》是管理学的入门教材。()正确答案:× 管理学课程简介(三) 1 ()是我们组织的基本的社会单元。 A、政府 B、家庭 C、学校

D、军队 正确答案:B 2 下面不属于读书报告内容的是()。 A、著作基本信息 B、作者主要观点 C、问题描述 D、个人心得 正确答案:C 3 政府、企业、慈善机构和学校都是组织。()正确答案:√ 4 成员目标是共同目标的实现基础。() 正确答案:× 组织及其机理(一) 1 创建组织的根本目的是()。 A、达成共同目标 B、单纯盈利 C、对抗其他组织 D、行使行政职能 正确答案:A 2 组织低效、混乱的表现不包括()。 A、资源浪费 B、内部消耗

C、精诚合作 D、争权夺利 正确答案:C 3 研究归纳推理的逻辑被称为归纳逻辑。() 正确答案:√ 4 组织的形成完全依赖于外部环境。() 正确答案:× 组织及其机理(二) 1 影响公司创业的关键因素不包括()。 A、销售渠道 B、共同目标 C、创业团队 D、组织规范 正确答案:A 2 最先开创组织管理理论研究的美国著名管理学家是()。 A、法约尔 B、巴纳德 C、泰罗 D、德鲁克 正确答案:B 3一个组织形成的外围促成因素不包括()。 A、领导人

APPlication,Session和Cookie的区别

APPlication,Session 和Cookie 的区别 方法信息量大小 保存时间应用范围保存位置 Application 任意大小整个应用程序的生命期 所有用户服务器端Session 小量,简单的数据用户活动时间+一段延迟时间(一般为20分钟) 单个用户服务器端Cookie 小量,简单的数据可以根据需要设定 单个用户客户端1.Application 对象 Application 用于保存所有用户的公共的数据信息,如果使用Application 对象,一个需要考虑的问题是任何写操作都要在Application_OnStart 事件(global.asax)中完成.尽管使用Application.Lock 和Applicaiton.Unlock 方法来避免写操作的同步,但是它串行化了对Application 对象的请求,当网站访问量大的时候会产生严重的性能瓶颈.因此最好不要用此对象保存大的数据集合 2.Session 对象 Session 用于保存每个用户的专用信息.她的生存期是用户持续请求时间再加上一段时间(一般是20分钟左右).Session 中的信息保存在Web 服务器内容中,保存的数据量可大可小.当Session 超时或被关闭时将自动释放保存的数据信息.由于用户停止使用应用程序后它仍然在内存中保持一段时间,因此使用Session 对象使保存用户数据的方法效率很低.对于小量的数据,使用Session 对象保存还是一个不错的选择.使用Session 对象保存信息的代码如下:// 存放信息Session["username"]="zhouhuan";//读取数据string UserName=Session["username"].ToString(); 3.Cookie 对象 Cookie 用于保存客户浏览器请求服务器页面的请求信息,程序员也可以用它存放非敏感性的用户信息,信息保存的时间可以根据需要设置.如果没有设置Cookie 失效日期,它们仅保存到关闭浏览器程序为止.如果将Cookie 对象的Expires 属性设置为Minvalue,则表示Cookie 永远不会过期.Cookie 存储的数据量很受限制,大多数浏览器支持最大容量为4096,因此不要用来保存数据集及其他大量数据.由于并非所有的浏览器都支持Cookie,并且数据信息是以明文文本的形式保存在客户端的计算机中,因此最好不要保存敏感的,未加密的数据,否则会影响网站的安全

全面从严治党是全面建成小康社会的根本保证

龙源期刊网 https://www.sodocs.net/doc/f5814073.html, 全面从严治党是全面建成小康社会的根本保证 作者:张明学 来源:《青年时代》2018年第02期 摘要:中国共产党“四个全面”战略布局之间是既相互贯通又紧密联系的统一体,即“全面建成小康社会”是处于统领地位的战略目标,而“全面深化改革”、“全面推进依法治国”、“全面从严治党”是实现这一目标的三大战略举措。本文试从全面从严治党和全面建成小康社会两个维度作为重点阐述二者之间的辩证关系,深刻理解全面从严治党是全面建成小康社会的根本保证这一原理。 关键词:四个全面;中国梦;党的建设 实现全面建成小康社会是一个需要打组合拳的新模式过程,我国是一个拥有13多亿人口的发展中大国,全面深化改革是实现全面建成小康社会的不竭动力,但是改革的过程是破旧立新,存在着“阵痛”,会“牵一发而动全身”,涉及的利益冲突和矛盾是方方面面的。常言说:“打铁还需自身硬”。要确保党始终成为推进各项事业改革的坚强领导核心,就必须全面从严治党,加强和改善党的领导。 一、全面深化改革必须不断加强和改善党的领导 首先,要牢牢把握全面深化改革的正确方向,必须在思想上从严治党,因为只有思想一致,才能步调一致。全面深化改革,就必须下狠心,开猛药,对一些已经固化的利益集团开炮,在整个过程中必须要认识到改革的艰难,如果不形成合力,就不可能获得真正的成功。要必须把广大党员干部的思想认识统一到中央的决策上来,把中央的各项部署分解和落实到广大干部群众实际工作中,确保全面深化改革能够沿着有利于党和人民事业发展的方向不断前进。一是要在思想上从严治党,就必须以思想理论建设为根本,重点抓好学习中央的各项决议决策和习近平总书记的系列讲话精神,引导和教育党员干部政治素养不断提高,促使大家矢志不渝为中国特色社会主义共同理想而奋斗;二是要以党性教育为抓手,以“三严三实”精神和“两学一做”活动为契机重点抓好党的优良传统和作风建设,教育引导党员干部特别是领导干部要牢固树立正确的世界观、权力观、事业观;三是要以道德建设为基础,重点抓好四德素养的提高,培育和践行各级干部对社会主义核心价值观的高度认同,教育引导党员干部做社会主义道德的示范者和维护者。 其次,全面深化改革过程中各项决策的形成和推进,必须加强和突显各级领导的责任意识。全面深化改革会牵涉到经济、政治、文化、社会、生态文明和党的建设等多个领域,会对一系列体制机制进行大刀阔斧的改革,是一项事关复杂利益进行不断调整的系统工程。因此,每一项改革措施的决策和推进,都需要站在全局的高度进行整体谋划、协调推进,在决策的过

java web之会话技术cookie+session

会话技术 1.什么是会话: 指用户开一个浏览器,访问一个网站,只要不关闭该浏览器,不管该用户点击多少个超链接、访问多少个资源,直到用户关闭浏览器,整个这个过程我们成为一次会话 2.实际情况: 张三打开浏览器,进入淘宝,买了2样东西;李四打开浏览器,进入淘宝,买了3样东西。当这两位结账时,结账的s e r v l e t如何得到张三和李四买的东西,并为他两分别结账? 3.使用会话保存数据 ?S e s s i o n ?C o o k i e 为什么需要C o o k i e? 情景1.张在访问某个网站的时候,看到了提示你上次登录网站的时间,而且不同用户上次登录时间不同,这个怎么实现 没有会话技术前:u s e r表每次用户登录就更新u s e r表里的时间 I d N a m e P a s s w o r d L o g i n_t i m e v i e w H i s t o r y 001A a A a2012-1-5 5:00:0022,33,2 5 002B b B b2012-3-12 6:00:0012,24,5 6 情景2.访问购物网的时候,能够看到曾经浏览过的商品,当然不同用户浏览过的商品不同 如果登录了,则可以用数据库 但如果没有登录那又怎么办?????? 情景3.保存登录密码及用户名 Cookie技术 1.服务器把每个用户的数据以cookie的形式写给用户各自的浏览器当用户使用浏览器再去访问服务器中的web资源时,就会带着各自的数据去 Servlet有一个Cookie类 Cookie(String name ,String value) 3.Cookie小结: ①Cookie在服务端创建 Cookie cookie = new Cookie(name,value); ②Cookie是保存在浏览器这端 response.addCookie(cookie); ③Cookie的生命周期可以通过cookie.setMaxAge(int second)来设置 Cookie默认生命周期是会话级别(即存储在浏览器的内存中) 如果没有设置setMaxAge(),则该cookie的生命周期当浏览器关闭时就挂了,setMaxAge(0) +response.addCookie(cookie),相当于删除Cookie 此时如果cookie文件内部只有该Cookie则,文件也一并删除;否则只删除该Cookie ④Cookie可以被多个浏览器共享

【知识学习】对“全面从严治党”的理解与体会

对“全面从严治党”的理解与体会 常言道:基础不牢,地动山摇。基层党组织发挥着战斗堡垒作用,基层党组织战斗力的强弱直接关系着党的整体战斗力的强弱。推动全面从严治党向基层延伸,认真落实习总书记讲话精神,才能厚植党的执政根基。 全面从严治党,必须加强基层组织建设,夯实基层基础。党的工作最坚实的力量支撑在基层,最突出的矛盾问题也在基层,必须把抓基层、打基础作为长远之计和固本之策,扎实推进“双基”建设,推动基层组织全面进步、全面过硬。 全面从严治党,必须推动党纪党规教育向基层延伸,唤醒党员党纪意识。开展“两学一做”学习教育,推动教育覆盖每一个基层党组织和党员,唤醒党员意识,促使党员干部尊崇党章、坚定理想信念,树立看齐意识,自觉培养高尚道德情操,守住纪律底线。 全面从严治党,必须把惩治腐败向基层延伸,维护群众切身利益。要教育引导党员干部强化规则意识、规矩意识,培养法治思维、法治理念、法治精神,带头遵守国家法律,带头遵守党规党纪,加强对违反制度行为的监督和查处。 全面从严治党,必须将管党治党意识,管党治党责任深入基层。首先基层党组织要树立正确的政绩观,把抓好党建作为最大的政绩,强化党建意识,对全面从严治党主动担责,认真履责,扎实尽责。坚持党建工作和中心工作一起谋划、

一起部署、一起考核,把每条战线、每个领域、每个环节的党建工作抓具体、抓深入,坚决防止“一手硬、一手软”。其次基层党组织主要责任人对党建工作要亲自抓、负总责,班子其他成员要切实落实党建工作责任和工作部署,细化到人,量化到岗,以责任落实推动工作落实。最后对工作不力,党建工作落后的地方和单位负责人,要及时进行诫勉谈话,对管党治党不力造成不良影响和严重后果的要严格问责,严肃处理。

管理学专业介绍

管理学专业介绍 管理学是系统研究管理活动的基本规律和一般方法的科学,学科分类上属一级学科。管理学是适应现代社会化大生产的需要产生的,它的目的是:研究在现有的条件下,如何通过合理的组织和配置人、财、物等因素,提高生产力的水平。管理学是一门综合性的交叉学科,更是现目前研究生报考的一大热点,更是跨专业报考的热点,每年都有相当数量的同学报考管理学。 管理学下设的二级学科有:企业管理,工商管理,会计学,,运筹与管理,旅游与酒店管理,公共事业管理,人力资源管理、市场营销等。 就业情况 适应在大中型企业特别是合资类与外向型企业、金融机构、政府机关、其它社会经济单位的信息管理部门、综合管理部门、计算中心等相关部门从事信息管理与信息系统的建设、运营等管理工作。 工商管理类 企业管理:各类工商企业、银行、证券公司等金融机构,会计师事务所等中介机构,以及政府经济管理部门。从事管理以及教学、科研方面的工作。 市场营销:到企业、科研院所、高等院校等从事管理决策、营销管理、销售、公关、品牌传播、理论研究与教学,或者是实际操作与管理性工作。 会计学:主要到企事业单位及政府部门从事会计实务以及教学、科研方面的工作。 财务管理:在高等院校和科研机构从事学术研究,在工商企业、金融机构、政府与事业单位、中介机构从事财务管理、咨询服务及其他相关经济管理工作。 人力资源管理:到企业、事业单位及政府部门从事人力资源管理以及教学、科研方面工作。 旅游管理:主要到各级旅游行政管理部门、旅游企事业单位从事旅游管理、经营或研究工作。 就业前景观察

管理学中部分二级学科近几年就业情况比较理想,比如工商管理里面的市场营销、会计学、企业管理、财务管理、人力资源管理等专业就业情况一直不错。公共管理类专业的研究生早些年就业非常一般,大部分到高校任教或者从事理论研究,但在未来几年估计公务员及协会等事业单位的就业会成为一个亮点。 具体来讲,在未来几年内,其就业前景主要包括: (1)传统管理职位,有很大一部分职业经理人的成长最开始来自基层锻炼经验。虽然说很多企业(一部分外资企业除外)目前开出的待遇水平让人难以接受,但从长远来看,对我们的发展还是非常有帮助的。特别是那些有心又有条件上MBA的同学来说——研究生就业环境恶化,但是具有一定年限工作经验的MBA毕业生在人力市场还是很受欢迎,如质量管理、专业项目管理等; (2)人力资源管理职位,以前的大学是没有专门开设人力资源管理专业的,它只是工商管理专业的一门专业课。近几年来,人力资源管理人员的地位一直是水涨船高,在公司的人员配置、战略决策、发展规划等关键问题上都处于智囊团位置,比如人力资源总监、薪酬经理、招聘经理、培训经理等; (3)市场营销职位,从历年人才市场统计数据来看,市场营销职位的需求经久不衰。销售职位的供需两旺一直是职场的一道风景线,即使在不同行业,市场营销类职位也总是招聘的热门,比如营销总监、营销主管、管理培训生、销售培训生等。 (4)物流管理职位,北京奥运会和上海世博会推动了中国物流业的进一步发展,招贤绣球四处高挂。而且,国内企业对物流行业成本压缩的诉求也刺激了物流人才的需求。目前,市场对物流人才的需求量超过600余万,被列为我国12类紧缺人才之一。可以说,中国的物流业正处在蓄势待发的阶段,极具市场潜力,前景十分广阔。大家可以报考报关员考试,或者是跟单员资格认证等。 (5)公共管理职位,这主要是公务员以及协会、学校等事业单位提供的就业机会,这也是管理学专业研究生的一个去向。尤其是目前一些机构推动改革,实现工作人员的知识化、年轻化,相信这部分就业会很快成为一大亮点。 (6)咨询类职位,这部分涉及到人力资源、市场营销、企业管理、物流管理等多个层面,除MBA、EMBA外,硕士研究生到咨询公司就业的也是比较多的。中国本土的咨询业还处于一个初步发展时期,文都教育认为,在未来五年内,大多数大中型企业都会需要外脑的帮助,咨询人员的需求会进一步扩大,更多管理学专业方面的高级人才会进入这个就业领域。

管理学原理

管理的定义: 1泰勒的定义:管理是一门怎样建立目标,然后用最好的方法经过他人的努力来达到的艺术。2法约尔的定义:管理就是计划,组织,控制,指挥,协调。3西蒙的定义:管理就是决策。4马克斯韦伯定义:管理就是协调活动。5美国管理协会的定义:管理是通过他人的努力来达到目标6本课程的定义:管理,就是通过计划、组织、领导和控制,协调以人为中心的组织资源与职能活动,以有效实现目标的社会活动。对管理定义的归纳 1强调作业过程:管理是计划、组织、领导、控制的过程;2强调管理的核心环节:管理就是决策;3强调对人的管理:管理就是通过其他人把事办好;4强调管理者个人作用:管理就是领导;5强调管理的本质:管理就是协调。 管理的属性 1管理二重性原理:管理既有自然属性,又有社会属性。2自然属性:同生产力相联系的管理的普遍性,是由生产力决定的。3社会属性:同生产关系相联系的管理的特殊性,是由生产关系决定的4管理的科学性:强调其客观规律性;5管理的艺术性:强调其灵活性与创造性。 管理者的定义 1关于管理者的传统观点:强调职位、职权、下属。2关于管理者的现代观点:强调对组织富有贡献的责任。3管理者的定义:管理者是指履行管理职能,对实现组织目标负有贡献责任的人。 管理者的分类

(1)按管理层次划分:高层管理者:决策层负责制定企业的现行政策,并计划未来的发展方向中层管理者:执行层执行企业组织政策,指挥一线管理人员或操作人员工作基层管理者:作业层一般只限于督导操作人员的工作,不会指挥其他管理人员 (2)按管理工作的性质与领域划分综合管理者;职能管理者。(3)按职权关系的性质划分直线管理人员;参谋人员。 管理者的素质:是指管理者的与管理相关的内在基本属性与质量。管理者的素质主要表现为品德、知识、能力与身心条件(管理者的技能,管理者的基本素质详情看书) 管理的环境:是指存在于社会组织内部与外部的影响管理实施和管理功效的各种力量、条件和因素的总和。2管理环境的分类:经济环境;技术环境;政治环境;社会与心理环境。一般环境与任务环境内部环境与外部环境管理与环境的关系:对应,交换,影响 管理的机制:是指管理系统的结构及其运行机理。2管理机制的特征:(1)客观性(2)自动性(3)可调性3管理机制的重要性:管理机制是决定管理功效的核心问题4管理机制以客观规律为依据。5管理机制以管理结构为基础和载体。一个组织的管理结构主要包括以下方面:(1)组织功能与目标;(2)组织的基本构成方式;(3)组织结构;(4)环境结构。分析内容:1有什么样的管理结构,就有什么样的管理机制。2有什么样的管理机制,就有什么样的管理行为,就有什么样的管理效果 1管理机制本质上是管理系统的内在联系、功能及运行原理。2类型:主要包括运行机制、动力机制和约束机制三个子机制。3运行机制的涵义。

深入理解新发展理念

深入理解新发展理念 创新、协调、绿色、开放、共享的发展理念,我在党的十八届五中全会和其他场合已经讲了不少,今天不从抓工作的角度全面讲了,而是结合历史和现实,结合一些重大问题,从理论上、宏观上讲讲。 第一,着力实施创新驱动发展战略。把创新摆在第一位,是因为创新是引领发展的第一动力。发展动力决定发展速度、效能、可持续性。对我国这么大体量的经济体来讲,如果动力问题解决不好,要实现经济持续健康发展和“两个翻番”是难以做到的。当然,协调发展、绿色发展、开放发展、共享发展都有利于增强发展动力,但核心在创新。抓住了创新,就抓住了牵动经济社会发展全局的“牛鼻子”。 坚持创新发展,是我们分析近代以来世界发展历程特别是总结我国改革开放成功实践得出的结论,是我们应对发展环境变化、增强发展动力、把握发展主动权,更好引领新常态的根本之策。 回顾近代以来世界发展历程,可以清楚看到,一个国家和民族的创新能力,从根本上影响甚至决定国家和民族前途命运。 16世纪以来,人类社会进入前所未有的创新活跃期,几百年里,人类在科学技术方面取得的创新成果超过过去几千年的总和。特别是18世纪以来,世界发生了几次重大科技革命,如近代物理学诞生、蒸汽机和机械、电力和运输、相对论和量子论、电子和信息技术发展等。在此带动下,世界经济发生多次产业革命,如机械化、电气化、自动化、信息化。每一

次科技和产业革命都深刻改变了世界发展面貌和格局。一些国家抓住了机遇,经济社会发展驶入快车道,经济实力、科技实力、军事实力迅速增强,甚至一跃成为世界强国。发端于英国的第一次产业革命,使英国走上了世界霸主地位;美国抓住了第二次产业革命机遇,赶超英国成为世界第一。从第二次产业革命以来,美国就占据世界第一的位置,这是因为美国在科技和产业革命中都是领航者和最大获利者。 中华民族是勇于创新、善于创新的民族。前面说到我国历史上的发展和辉煌,同当时我国科技发明和创新密切相关。我国古代在天文历法、数学、农学、医学、地理学等众多科技领域取得举世瞩目的成就。这些发明创造同生产紧密结合,为农业和手工业发展提供了有力支撑。英国哲学家培根这样讲到:印刷术、火药、指南针,这3种发明曾改变了整个世界事物的面貌和状态,以致没有一个帝国、教派和人物能比这3种发明在人类事业中产生更大的力量和影响。一些资料显示,16世纪以前世界上最重要的300项发明和发现中,我国占173项,远远超过同时代的欧洲。我国发展历史上长期处于世界领先地位,我国思想文化、社会制度、经济发展、科学技术以及其他许多方面对周边发挥了重要辐射和引领作用。近代以来,我国逐渐由领先变为落后,一个重要原因就是我们错失了多次科技和产业革命带来的巨大发展机遇。 当今世界,经济社会发展越来越依赖于理论、制度、科技、文化等领域的创新,国际竞争新优势也越来越体现在创新能力上。谁在创新上先行一步,谁就能拥有引领发展的主动权。当前,新一轮科技和产业革命蓄势

世界主要管理学家简介及其主要思想1

1、管理过程之父法约尔法国1841-1925 西方古典管理理论在法国的最杰出代表亨利·法约尔(Henry Fayol)法国科学管理专家。管理学先驱之一 法约尔的管理功能理论认为管理功能包括计划、组织、命令、协调和控制。管理企业的六项基本活动是:技术、商业、财务、安全、会计和管理(核心)。管理不是专家或经理独有的特权和责任,而是企业全体成员(包括工人)的共同职责,只是职位越高,管理责任越大。他在实践基础上总结出14条管理原则,即分工、职权与职责、纪律、统一指挥、统一领导、公益高于私利、个人报酬、集中化、等级链、秩序、公正、保持人员的稳定、首创精神、集体精神。其主要内容包括:任何一个下属组织只应该接受一个上级的命令,这是组织统一行动,协调力量和一致努力的必要条件;从最高权力层直至低层管理人员应组成类似金字塔式的组织,使发出命令、解决争端和传递信息都经过法定的渠道;一个管理者能有效地直接领导、指挥和监督的下属人数的极限一般为12个;组织应自上而下地管理,最终的管理责任在上层,而不是将管理责任分散,甚至消失在下层;管理的权力和责任共存,责任是权力的自然结果和必不可少的对等物,责任下放了,权力也必须下放。法约尔的管理功能理论在欧洲有深远的影响,也曾为美国传统行政学派所接受。 2、彼得·德鲁克(Peter F.Drucker) (1909.11.19~2005.11.11)一生共著书39本,在《哈佛商业评论》发表文章30余篇,被誉为“现代管理学之父” 1954年,德鲁克提出了一个具有划时代意义的概念——目标管理(Management By Objectives,简称为MBO),它是德鲁克所发明的最重要、最有影响的概念,并已成为当代管理学的重要组成部分。 目标管理的最大优点也许是它使得一位经理人能控制自己的成就。自我控制意味着更强的激励:一种要做得最好而不是敷衍了事的愿望。它意味着更高的成就目标和更广阔的眼界。目标管理的主要贡献之一就是它使得我们能用自我控制的管理来代替由别人统治的管理。 3、赫伯特·西蒙(Herbert·A·Simon,1916~?)美国管理学家和社会科学家 为决策贯彻管理的全过程,管理就是决策,组织就是决策,组织是由作为决策者的个人所组成的系统。综观其著作,除上述观点为组织方面的外,其余主要是发展了决策的科学方法体系。 4.哈罗德·孔茨(H.Koontz);美国管理学家,管理过程学派的主要代表人物之一 孔茨利用这些管理职能对管理理论进行分析、研究和阐述,最终得以建立起管理过程学派。孔茨是管理过程学派的集大成者,他继承了法约尔的理论,并把法约尔的理论更加系统化、条理化,使管理过程学派成为管理各学派中最具有影响力的学派。 管理过程学派的主要特点是将管理理论同管理人员所执行的管理职能,也就是管理人员所从事的工作联系起来。他们认为,无论组织的性质多么不同(如经济组织、政府组织、宗教组织和军事组织等),组织所处的环境有多么不同,但管理人员所从事的管理职能却是相同的,管理活动的过程就是管理的职能逐步展开和实现的过程。因此,管理过程学派把管理的职能作为研究的对象,他们先把管理的工作划分为若干职能,然后对这些职能进行研究,阐明每项职能的性质、特点和重要性,论述实现这些职能的原则和方法。管理过程学派认为,应用这种方法就可以把管理工作的主要方面加以理论概括并有助于建立起系统的管理理论,用以指导管理的实践。 5、亚当·斯密(1723~1790)是经济学的主要创立者。 6、泰罗(Frederick Winslow Taylor)(1856-1915)是美国古典管理学家,科学管理理论的主要倡导者,被后人尊称为“科学管理之父”。科学管理原理》是他的代表作,较为全

相关主题