TP-Link T2700G-28TQ T2700G-28TQ User Guide V1 - Page 182

RIP Message Format, Supporting masks, route summarization and Classless Inter-Domain Routing CIDR.

Page 182 highlights

information of natural networks such as Class A, B, and C. That is why RIPv1 does not support discontinuous subnets. RIPv2 is a classless routing protocol. Compared with RIPv1, RIPv2 has the following advantages.  Supporting route tags. Route tags are used in routing policies to flexibly control routes.  Supporting masks, route summarization and Classless Inter-Domain Routing (CIDR).  Supporting designated next hops to select the best next hops on broadcast networks.  Supporting multicast routing update to reduce resource consumption.  Supporting plain text authentication and MD5 authentication to enhance security. Note: RIPv2 has two types of message transmission: broadcast and multicast. Multicast is the default type using 224.0.0.9 as the multicast address. The interface working in the RIPv2 broadcast mode can also receive RIPv1 messages.  RIP Message Format 1) RIPv1 message format An RIPv1 message consists of a header and up to 25 route entries. The following figure shows the format of RIPv1 message. Figure 10-24 RIPv1 Message Format The detailed explanations of each field are stated as following:  Command: Type of message. 1 indicates request, and 2 indicates response.  Version: Version of RIP, 0x01 for RIPv1.  AFI: Address Family Identifier, 2 for IP.  IP Address: Destination IP address of the route. It can be a natural network, subnet or a host address.  Metric: Cost of the route. 2) RIPv2 message format The format of RIPv2 message is shown as the following figure. It is similar to RIPv1. 170

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170
information of natural networks such as Class A, B, and C. That is why RIPv1 does not support
discontinuous subnets.
RIPv2 is a classless routing protocol. Compared with RIPv1, RIPv2 has the following advantages.
Supporting route tags. Route tags are used in routing policies to flexibly control routes.
Supporting masks, route summarization and Classless Inter-Domain Routing (CIDR).
Supporting designated next hops to select the best next hops on broadcast networks.
Supporting multicast routing update to reduce resource consumption.
Supporting plain text authentication and MD5 authentication to enhance security.
Note
RIPv2 has two types of message transmission: broadcast and multicast. Multicast is the default
type using 224.0.0.9 as the multicast address. The interface working in the RIPv2 broadcast mode
can also receive RIPv1 messages.
RIP Message Format
1)
RIPv1 message format
An RIPv1 message consists of a header and up to 25 route entries. The following figure shows the
format of RIPv1 message.
Figure 10-24 RIPv1 Message Format
The detailed explanations of each field are stated as following:
Command: Type of message. 1 indicates request, and 2 indicates response.
Version: Version of RIP, 0x01 for RIPv1.
AFI: Address Family Identifier, 2 for IP.
IP Address: Destination IP address of the route. It can be a natural network, subnet or a
host address.
Metric: Cost of the route.
2)
RIPv2 message format
The format of RIPv2 message is shown as the following figure. It is similar to RIPv1.