大规模网络路由技术

[RTA]isis

[RTA-isis-1]is-level level-1

[RTA-isis-1]network-entit01.1111.1111.1111.00

[RTA-isis-1]interface serial 2/0

[RTA-Serial2/0]isis enable 1

[RTA-Serial2/0]isis cost 1

[RTB]isis

[RTB-isis-1]is-level level-1

[RTB-isis-1]network-entit01.2222.2222.2222.00

[RTB-isis-1]interface serial 1/0

[RTB-Serial1/0]isis enable 1

[RTB-Serial1/0]isis cost 1

[RTB-Serial1/0]interface Ethernet 0/0

[RTB-Ethernet0/0]isis enable 1

[RTB-Ethernet0/0]isis cost 1

[RTC]isis

[RTC-isis-1]is-level level-1

[RTC-isis-1]network-entit01.3333.3333.3333.00

[RTC-isis-1]interface Ethernet 0/0

[RTC-Ethernet0/0]isis enable 1

[RTC-Ethernet0/0]isis cost 1

[RTC-Ethernet0/0]interface Ethernet 0/1

[RTC-Ethernet0/1]isis enable 1

[RTC-Ethernet0/1]isis cost 1

各路由器路由稳定后，RTA 上 IS-IS 路由 192.168.3.0/24 的开销是 _。（含图）