Make your own free website on


        We Engineers move the world


Exam Details




Email: Webmaster







PROXY SERVER 2.0 -Cramsession


Minimum requirements for Proxy Server 2.0:

         486 or higher CPU

         24mb RAM (with Intel processor)

         32mb RAM (with RISC processor)

         10mb free hard drive space

         5mb required minimum free hard drive space for caching. (Although it is recommended you have 100MB + 0.5MB per client)

         NT Server 4.0 with Service Pack 3 installed.

SETUP.EXE can be used to install Proxy Server. Options:

         /r - Reinstall Proxy Server

         /u - Uninstall Proxy Server

         /k "keynumber" - Specifies the CD Key

  MPSSETUP.LOG - Log file displaying problems found during server installation.

Proxy Server 2.0 is added into the MS Management Console (Internet Service Manager) administration utility.

Client installation

Client software can be installed through the //servername/mspclnt share and running SETUP.EXE, or by connecting to http://servername/msproxy and running the installation program.

  MPCSETUP.LOG - Log file displaying problems found during client installation.

The following items are installed with the client software:

         WinSock Proxy client application

         MSPCLNT.INI - Contains client configuration information.

         MSPLAT.TXT - Contains the Local Address Table.


Recommended cache space allocation is 100mb + .5mb free disk space per client.

The default setting for cache is 100mb when the drive has at least 150mb free hard drive space.

Caching can only be performed on an NTFS partition. It cannot be performed on a FAT partition.

To convert a FAT partition to NTFS to allow caching, use the CONVERT.EXE utility.

Connections requiring authentication or SSL connections will not be cached.

  Passive caching - All objects are cached. Cached objects will be removed after their TTL has expired. Objects will then be re-cached only when a client accesses that site again.

  Active caching - Frequently requested objects are retrieved from the Internet by the proxy server when the TTL of the object in cache is getting ready to expire.

Caching options:

Cache expiration policy

         Updates are more important - Lowers cache performance to keep popular pages updated frequently.

         Equal importance - Balances cache performance with cache updates.

         Fewer network accesses are more important (more cache hits) - Provides best cache performance.

Enable active caching

         Faster user response is more important - Saves less cache, but updates what is saved very frequently. Causes more users to access data from the Internet rather than cache.

         Equal importance - Balances cache performance with cache updates.

         Fewer network accesses are more important - Allows least amount of Internet traffic and will not update cache as often.

To limit the size of cache objects, use expired objects in the cache, or change an object's TTL, set the proper options in the page accessed through the Web Proxy Service Properties window by clicking the Caching tab, then click Advanced.

  Cache Filters - List of specific URLs that are in the cache. You can edit the cache list in the Web Proxy Service Properties window by clicking the Caching tab, Advanced, then click Cache filters.

LAT (Local Address Table)

  LAT - Contains IP addresses of the internal network and IP address of the proxy server.

  MSPLAT.TXT - Contains the Local Address Table. The master copy of this file is stored on the server, and can be downloaded to client systems.

  LOCALLAT.TXT - Custom LAT for clients that need access to network ranges not specified in the MSPLAT.TXT

You can construct the list of internal IP addresses by clicking Construct Table.

Add Internal IP ranges from your network to specify addresses of clients that will be connecting throught the proxy server.

IP ranges can be changed in the individual service's properties by clickin the Local Address Table button.

CARP (Cache Array Routing Protocol) and Multiple Proxy Servers

  CARP - Multiple proxy servers are configured in an array to provide a single logical cache. These servers communicate between each other, so that each server knows the exact contents of each other. This disallows cache duplication.

Uses HTTP to communicate.

CARP can be implemented on clients using PAC - Proxy Auto-Config file.

Proxy arrays use an array membership list. They use TTL to determine when to check for active servers, and maintains the list of active servers in the array membership list.

Array manager is used to maintain the array membership list. List includes TTL until next check, URL to receive array information for a remote manager, and load factors for each server.

The proxy server will query array for a new table when TTL expires.

  Heirarchical routing - Requests are forwarded from a downstream proxy or array to an array of upstream proxies when they cannot be serviced. One hop is performed in each array before being forwarded to the next level.

  Distributed routing - One member of the array will answer a request received by another member of the array, when it is determine