IS-IS ROUTING PROTOCOL
(Intermediate System-to-Intermediate System)
*Link state protocol ve IGP protocol and runs over CLNS
*ISIS doen not have phsichal (Necessary for Ospf )
*Can support 1000 router in IS-IS area . (OSPF 50 only )
*Using PARTIACL ROUTE Calculation (rpc) algorithma in IS-IS ip routing table
Use SPF algorithm for connection to neighbors.
*It is possible so mye configuration than OSPF
*Using OSI Model (IS-IS )
*Use MD5 authentication
Send ``IS HELLO`` packets to neighbors
IS IS LEVELS
L1 (Routers) : For comminaction same areas
L2 (Routers): communication with L2 ve L1 /L2, backbone /transit level
L1 / L2 (Routers):Can communication L1 and L2
CLNS (Connection Less mode Newtwork Service) Types
*Clns operates at layer 3
*Clnp and TP4 are layer 4 protocols
Important: IS-IS developed by DEC.
*IS-IS using NSAP Addressing
*IS-IS lsdb are built using LSPs (Link state Pdus ) and IS-IS can have 1 or 2 database on a router
There are 3 categories of IS-IS PDU
Hello PDUs
Link state PDUs
Sequence Number PDUs
TLV TYPES
Type 1 :Area Address
Type 2 : IIS neighbors
Type 6:system neighbor
Type 8: Padding
Types 10 : Authentication
Type 128: ip internal Reachability
Types 129
Types 130
Type 211: Restart
LSP TYPES
LSP1
LSP2
*PDU :are sent every 9 seconds default but can be change
IS-IS DEFAULT METRICS
Doe not take into account speed
All physical interfaces have metric of 10
Loopback interfaces have a metric of 0
DEault Metric cost for main link: 1 GB
Backup link is 10 MB
***Max metric for IS IS is 1023
IS-IS level 1 internal route:15
IS-IS level 2 internal route :18
IS-IS level 1 external route:160
IS-IS level 2 external route:165
Metric s for ISIS
Delay
Error
Expense
Configuration
At Srx1
Edit protocols isis
Set interface fe 0/0/0.0
Set interfaces fe 0/0/1.0
Set interfaces fe 0/0/7.0
Top
Edit interfaces
Set interface fe 0/0/0.0 family iso
Set interface fe 0/0/1.0 family iso
Set interface fe 0/0/7.0 family iso
Commit
At Srx3
Edit protocols isis
Set interface fe 0/0/0.0
Top
Edit interfaces
Set interface fe 0/0/0.0 family iso
Commit
Show route protocol isis
CREATING AREAS