SWG Networking & Engineering

Sunnyslope Design Deliverables

 

IGRP (Interior Gateway Routing Protocol) is a Cisco distance-vector based routing protocol.  IGRP uses metrics to determine the best route to a network.  Routing updates are sent at 90-second intervals, unless otherwise specified. Delay, bandwidth, reliability are also used by IGRP.  Using IGRP allows the use of multiple paths between two networks. IGRP makes adjustments according to calculation of the best path.  Routing with an Autonomous system (AS) is a collection of networks under a common administration sharing a common routing strategy. 

Autonomous Systems are subdivided into routes: Interior routes are attached to router interface between the subnets.  System routes are to other major networks within the AS, but they do not include subnetting.  Exterior routes are to network that are outside of the AS; they will use the gateway as the last resort.

Pro's Con's
  • Its ability to automatically handle indefinite, complex topologies with stability. (Routing Loops)
  • Flexibility for segment, which may have differEnt bandwidth and delay.
  • Scalability to function in large to small networks.
  • Link quality and speed is more flexible than RIP.
  • More complex configuration of the router. Two basic step process (router commands and protocols)
  • May have increased topology convergence time, with the use of holddowns.

 

VLAN (Virtual local-area network) is a grouping of users or devices.  Functions, departments, applications, etc can group users.  Groups/Users can be created regardless of physical location allowing for easy movement or adding of computers.  VLAN’s are created through a switch by software. The Sunnyslope Campus has two separate VLAN’s; Curriculm and Administration.

Pro's Con's
  • VLANS cover the entire network
  • Separation of users /groups regardlless of location.
  • Controlled broadcast and increased security by the turning on and off of ports.

 
  • More upfront administration to implement. Need to build database within VLAN software.
  • switches need to be configured

 

PPP (Point-to-Point) is a common data-link encapsulation associated with WAN lines.  It is a standard serial-line encapsulation.  PPP checks for link quality during connection.  It also supports authentication by using PAP (Password Authentication Protocol) and CHAP (Challenge Handshake Authentication Protocol).  CHAP has an advantage over PAP because it will be encrypted by CHAP and cannot be detected by a network analyzer.  If a password is not encrypted, then it is not secure.

 

Pro's Con's
  • Provides a reliable backup link.
  • Provides access to digital video, circuit-switched data and telephone network services by using normal telephone network that is circuit -switched.
  • More upfront administration to implement. Need to build database within VLAN software.
  • Switches need to be configured.

ISDN (Integrated Services Digital Network)  can be used for cost-effective remote access to corporate networks.  It provides support for voice and video as well as a backup for another type of link.  If a remote site is small with low demand of services ISDN would be the logical choice.  ISDN is needed in the Washington School District sencerio as a back-up link in the case of a main network connection loss.  User who will be dialing in from a remote site will also need ISDN.

 

Pro's Con's
  • Provides a reliable backup link
  • Provides access to digital video, circuit-switched data, and telephone network services by using normal telephone network that is circuit-switched
  • ISDN is slower than T1 lines, uses a B channel of 64 kbps.
  • Security issues because of connection over public telephone lines
  • Isdn uses only HDLC encapsulation type

Frame Relay is a high performance, efficient data-link technology used in networks throughout the world.  Frame Relay will be implemented into Washington School District by why of Frame Relay switching equipment in the Central Office of the telecommunications carrier. Speed between 56 kps and 1.544 Mbps are typical.  This data-link technology can support lower and higher speeds.   Multiplexing abilities are capable with Frame Relay providing a means for many logical data conversations.  These conversations are referred as virtual circuits, through a shared medium.  By assigning DLCI’s ( Data-link connection identifier) that identifys a circuit between the source and destination device.  Frame Relay switch maps the DLCI’s between each pair of routers to create a PVC (permanent virtual circuit). 

Frame Relay also provides more flexible and efficient use of available bandwidth.  It allows users to share bandwidth at a reduced cost.

Pro's Con's
  • Provides a flexible method of connecting LAN’s over Frame Relay WAN links
  • Provides packet-switching data communication between user device
  • Split horizon reduces

 
  • Configuration of router
  • Configuration for more enhancement of router

Novell IPX is a Net Ware network layer protocol, which used for transferring data from servers to the workstation.  IPX is connection-less which does not require acknowledgement for each packet and also operates within the same network.  It operates similar to TCP/IP provided you have a multiprotocol router.  IPX is used in a client/server environment. The addressing structure is network node and the logical address contains an interface MAC address.  IPX supports multiple data-link encapsulations (frame type), which are supported by Cisco routers.  This multiple encapsulation reduces equipment expense, configuration complexity and eases transition from one frame type to another.

WAN (Wide-area network) operate beyond the LAN geography.  WAN’s must use a service provider.  Telephone and data services are the most commonly used WAN services.  The Washington School District WAN will have a POP (point of presence) in each of it’s schools MDF that will connect all of its schools and administration offices together for the purpose of delivering and transferring of data.  Access  to the Internet can be obtained from any site in WSD.

The WAN’s link to the Internet is a Frame Relay PVC (Permanent virtual circuit) running at T1 line speed for the district.   T1 line speed has a signal standard of DS1 and a bit rate capacity of 1.544 Mbps. 

The networking protocol for the Washington School District will be TCP/IP (Transmission Control Protocol/Internet Protocol) and Novell IPX (Internet Packet Exchange).  TCP/IP is the standard for internetwork communications and serves as a transport protocol for Internet.  As a universal protocol it allows computers to communicate globally. This protocol includes specifications for applications such as e-mail, remote login, terminal emulation and file transfer.  TCP/IP is a connection-oriented, flow controlled reliable protocol by breaking messages into segments, then reassembling them at the destination, any segment that was not received will be resent.  The process is called sliding window. Sliding window makes the use of bandwidth more efficient by allowing more data to be transmitted.

IP provides connection-less, best-effort delivery routing of datagrams. (Looks for a way to move datagram to their destination).  Features include addressing, fragmentation and reassembly and security.

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