Shulou(Shulou.com)06/03 Report--

Different network segment communication-routing: OSI network reference model for the third time: network bits.

-Router-"routing entry -" routing table

Type network/mask [command]

Type: how the router obtains this routing entry:

1 > directly connected [automatic generation]

2 > static [manually configured by administrator]

3 > dynamic protocols:

IGP: interior Gateway Protocol-used exclusively within the company

-DV (distance vetor, distance vector routing protocol)

RIP-routing information protocol, routing Information Protocol [16]

IGRP-internal gateway routing protocol, Interior Gateway routing Protocol

EIGRP-extended IGRP, extended IGRP

-LS (link state, link-state routing protocol)

ISIS-intermedia system-intermedia system, intermediate system to intermediate system

OSPF-open shortest path first, an open shortest path first protocol

EGP:external gateway protocol, external Gateway Protocol-designed for BGP-border gateway protocol between networks, Border Gateway Protocol

WEB-> tcp 80

DHCP-- > eNSP-> belongs to OSI layer 7, udp67/68

RIP-> udp 520, which belongs to the OSI module layer 7-application layer

Process number in RIP protocol:

1. Multiple RIP processes can be run at the same time on the same router.

2. Different processes are distinguished by the process number. The range of values is 1-65535.

3. On the same router, different processes are isolated from each other and cannot communicate directly by default.

Note:

When communicating with the RIP protocol between different routers, there is no need to care about whether the process number is the same.

Whether it's the same or not, you can communicate directly.

Version number in RIP protocol:

1. Contains 2 versions, version 1, and does not support subnet mask

Version 2 contains the subnet mask

3. Huawei's equipment defaults to the version 1 used.

4. All router devices in the network should use the same version of RIP. It is strongly recommended that RIPv2 be used.

The difference between RIPv1 and RIPv2:

RIPv1: classful routing protocols (without mask when declaring routing information) / broadcast updates (255.255.255.255)

Does not support VLSM/ automatic route summarization, cannot be turned off / does not support discontiguous subnets

RIPv2: classless routing protocol (with mask when announcing routing information) / Multicast update (224.0.0.9) / support for VLSM/

Automatic summarization can be turned off, manual summarization / support for discontiguous subnets

The Network command in the RIP protocol:

0. The network command works only for "directly connected routes" local to the device.

1. Only the network segments that have been network can be loaded into RIP messages.

2. Only the link represented by the network segment is qualified to send and receive RIP messages.

The work Unit of RIP Protocol-- message

1. Request: request a routing message from another device

2. Respone: response message, which is equivalent to an update message containing routing entries

Response speed of RIP protocol network: slow

1. Periodic updates

2. The update cycle is 30s.

Display rip update time: 30s, age time: 180s

Introduction to the attributes of RIP routing:

1. Preference. The default value is 100; this attribute does not change as the route is passed.

2. Cost, in RIP, can also be called hop (hop count).

By default, RIP routes pass through each router, metric/cost

Will automatically add one.

The maximum value is 16. When the metric/cost of the route RIP reaches 16:00, the route is no longer valid and cannot appear in the routing table. Note: we can modify (increase) the metric/cost value of the route in the corresponding direction of each interface of the router's delivery path: interface gi0/0/2 rip metricin {numerical}-- > increase the specified "value" for the cost of the RIP route received on this port. Interface gi0/0/1 rip metricout {value}-> add the specified "value" to the cost of the RIP route sent out on the port; 3. By modifying the attributes of the RIP route, you can achieve the "backup" of the RIP route entry. Note: essentially, by modifying the cost of a RIP route, you can also achieve a "backup of the route", or "floating route" as we learned earlier.

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