Network Protocols

NETWORK PROTOCOLS

PRESENTATION RIP (ROUTING INFORMATION PROTOCOL) BSC.COMPUTER SCIENCE LEVEL.400 BAAH GEOFFREY JNR. INDEX:1012497

TYPES OF ROUTING STATIC ROUTING Uses a route that a network administrator enters into the router manually

DYNAMIC ROUTING Uses a route that a network routing protocol adjust automatically for topology or Traffic changes

DEFAULT ROUTING Uses a route that allows a stub network to reach all known network against it

ROUTING INFORMATION PROTOCOL (RIP) • The Routing Information Protocol (RIP) is one of the most commonly used Interior Gateway Protocol on internal networks which helps a router dynamically adapt to changes of network connections by communicating information about which networks each router can reach and how far away those networks are. Although RIP is still actively used, it is generally considered to have been obsolete by Link-state routing protocol such as OSPF.

ROUTING INFORMATION PROTOCOLS (RIP) • The Routing Information Protocol (RIP) provides the standard IGP protocol for local area networks, and provides great network stability, guaranteeing that if one network connection goes down the network can quickly adapt to send packets through another connection. The following subsections describe how

.

RIP was invented and how RIP works

HOW RIP WAS INVENTED The Routing Information Protocol (RIP) was written by C. Hedrick from Rutgers University in June 1988, and has since become the most common Internet routing protocol for routing within networks. • RIP is based on the computer program "routed", which was widely distributed with the Unix 4.3 Berkeley Software Distribution (BSD) operating system, and became the de-facto standard for routing in research labs supported by vendors of network gateways. • All RIP routing protocols are based on a distance vector algorithm called the Bellman-Ford algorithm, after Bellman's development of the equation used as the basis of dynamic programming, and Ford's early work in the area.

HOW RIP WORKS What makes RIP work is a routing database that stores information on the fastest route from computer to computer, an update process that enables each router to tell other routers which route is the fastest from its point of view, and an update algorithm that enables each router to update its database with the fastest route communicated from neighboring routers:

RIP version 1 (RIPv1). • This is a simple distance vector protocol. It has been enhanced with various techniques, including Split Horizon and Poison Reverse in order to enable it to perform better in somewhat complicated networks. • The longest path cannot exceed 15 hops. • RIP uses static metrics to compare routes. • The maximum datagram size is 512 bytes not including the IP or UDP

.

headers

RIP version 1 (RIPv1). • The original specification of RIP uses classful routing. The periodic routing updates do not carry subnet information, lacking support for variable length subnet masks (VLSM). This limitation makes it impossible to have different-sized subnets inside of the same network class. In other words, all subnets in a network class must have the same size. There is also no support for router authentication, making RIP vulnerable to various attacks.

RIPv1 ENTRY TABLE

RIPv1 entry table. An array of RIPv1 e * Address-family identifier (AFI)—Specifies the address family used. RIP is designed to carry routing information for several different protocols. Each entry has an address-family identifier to indicate the type of address being specified. The AFI for IP is 2.

0 0 0 0 0 0

* Address—Specifies the IP address for the entry.

* Metric—Indicates how many internetwork hops (routers) have been traversed in the trip to the destination. This value is between 1 and 15 for a valid route, or 16 for an

RIP version 2 (RIPv2). • This version added several new features. • External route tags. • Subnet masks. • Next hop router addresses. • Authentication. • Multicast support.

RIPv2 ENTRY TABLE

R IPv2entrytable. A narrayofR IPv2entries. E 0 0

0 1

0 2

0 3

0 4

RIP VERSION 2 (RIPv2) Due to the deficiencies of the original RIP specification, RIP version 2 (RIPv2) was developed in 1993 and last standardized in 1998. It included the ability to carry subnet information, thus supporting Classless Inter-Domain Routing (CIDR). To maintain backward compatibility, the hop count limit of 15 remained. RIPv2 has facilities to fully interoperate with the earlier specification if all Must Be Zero protocol fields in the RIPv1 messages are properly specified. In addition, a compatibility switch feature allows fine-grained interoperability adjustments.

CONTI • RIPv2 is a classless routing protocol built as an extension to RIPv1 • It supports modern networks’ use of VLSM and authentication • In addition, it provides backward compatibility with RIPv1 when configured correctly • Still, RIPv2 suffers from all the pitfalls of distance-vector routing protocols

ADVANTAGES & DISADVANTAGES OF RIP

• ADVANTAGES • Compatible with several network machines • Process load small

DISADVANTAGES • Subnet mask information is not carried (Incompatible with VLSM- variable length subnet masks ) • Can only deal with maximum 15 numbers of hops

• THANK