Shulou(Shulou.com)06/01 Report--

Basic knowledge of IS-IS

IS-IS: that is, (Intermediate system to intermediate system) internal network to internal network. (to put it bluntly, it is the interior gateway protocol).

ISIS: uses the SPF spanning tree algorithm, which is similar to OSPF routing and is a link-state protocol.

IS-IS: used in CLNS and IP environments) belongs to the network layer, but works at the data link layer.

Supported link states: Ethernet .PPP, HDLC

ES-IS: end system

IS-IS: routers, switches and other network equipment

Information about routes or interfaces commonly used in ISIS (commonly used)

Relationships between 1.L1:ISIS internal routers.

2.L2 connects multiple regions or different systems is the backbone relationship.

3.L1/L2:Backbone area.

Backbone regions are contiguous and cannot be divided.

1.L0:ISIS system IS routing information to terminal information.

2.L1: a connection established by a router within an area. (area intra-area router)

3.L2: a relationship established between different regional systems. (mainly backbone areas)

4.L1/L2: ability to accept and process routing information sent by L1 and L2 routers. (similar to OSPF's ABR)

5.L3: the ability to transmit routing information between different areas (AS).

Routing information transmitted between the router and the routing interface

Routing interface L1L2L1/L2L1L1 × L1L2 × L2L2L1/L2 × × L1/L2

Message type of ISIS (9 types of messages)

Hello

Level-1 LAN IIH ISIS HELLOW

Level-2 LAN IIH ISIS HELLOW

P2P IIH ISIS HELLOW

LSP (link state PDU) link state

Level-1 LSP

Level-2 LSP

SNP sequence number message LSDB database synchronization, send summary information.

CSNP: full serial number message

Level-1 CSNP

Level-2 CSNP

PSNP: incomplete serial number message

Level-1 PNSP

Level-2 PNSP

ISIS database

Use pseudo-nodes to synchronize the database (DIS)

DIS: intermediate systems can be specified (can be preempted).

The broadcast network can achieve database synchronization more effectively.

A pseudo node is a virtual database.

Database synchronization based on DIS

The finite order of DIS can be modified.

ISIS address structure

IDP DSP

IDP network number

AFI

IDI

High order DSP subnet mask

System ID code / serial number

SEL 00

Network bit mask / host bit

47.0001 0000.0000.0001. 00

Network number System ID SEL

47 public network

49 Private Network

The performance of ISIS forming neighbors

1. Same level

two。 Same area

3. Same network segment

ISIS routing forwarding policy

1.ISIS path selection

2.ISIS routing addressing routing

3. Look for the route exit in this area when sending data

4. Find the exit of the target area

5. Find the shortest path in the target area

ISIS supports authentication

1. Port area: authenticate hello messages.

two。 Regional authentication: authenticate level 1 SNP and LSP messages.

3. Routing authentication: authenticate the backbone area.

Basic configuration of ISIS routing

1. Create an ISIS address

Isis 1 (default ISIS number is 1)

Network-entity 47.0001.0000.0000.0001.00

Quit

two。 Declare under the port

Interface GigabitEthernet0/0/0

Ip address 10.10.123.1 255.255.255.0

Isis enable 1 (can be customized according to specific configuration)

Quit

Authentication of ISIS rout

Port-based authentication

[Huawei] int GigabitEthernet 0/0/0

[Huawei-GigabitEthernet0/0/0] isis authentication-mode simple huawei

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