Maximum path

[Pramod.purohit]

Hello everyone,

I have gone through Cisco press book of CCNA and have some confusion while studying load balaning. in book there are two things mentioned process-switching and fast-switching interfaces on router. can anyone please explain what does it means.

also in the book the max path supported by routing protocols such as RIP, OSPF, and EIGRP is 16 there.

Please confirm

[elphrank0]

15 is the max, 16th is unreachable..

[anurag007]

process switching
its bascically the process of luking into each packet see its source table and destination ip den send arp gets other mac adress and then forward the packet...
so wen next packet come same process is repeated...
Disadvantage
Its is slow process ..becoz he wil luk into each packet ....

Fast switching
it wil so de same but only to first packet and den store the info in cache...so process become fast

Disadvantage
Perpacket load sharing...not possible

CEF(cisco express forwarding) LIFE SAVER(LOL)
it wil not even luk into first packet it wil bulid FIB(forward info base)..and with the help of FIB it wil build ADJ table and store that in cache...

disadvantage
more memory is needed....
cisco proprietary

MPLS(industry standard)
same as CEF but its industary standarad


hope this helps u out.....

[Fuzz]

15 is the max, 16th is unreachable..

With RIP yes, but OSPF and EIGRP use more complicated metrics, and they support much larger topologies as a result. 16 hops is not unreachable when using either of these protocols.

[Pramod.purohit]

Hello,

I am not asking maximum hop count I am asking for number of equal cost path for same destination supported by each routing protocol.

[anurag007]

if the router receives and installs multiple paths with the same administrative distance and cost to a destination, load-balancing can occur.

The number of paths used is limited by the number of entries the routing protocol puts in the routing table.

Four entries is the default in IOS for most IP routing protocols with the exception of Border Gateway Protocol (BGP), where one entry is the default.
The IGRP and EIGRP routing processes also support unequal cost load-balancing. You can use the variance command with IGRP and EIGRP to accomplish unequal cost load-balancing. Issue the maximum-paths command in order to determine the number of routes that can be installed based on the value configured for the protocol. If you set the routing table to one entry, it disables load balancing

[Pramod.purohit]

process switching
its bascically the process of luking into each packet see its source table and destination ip den send arp gets other mac adress and then forward the packet...
so wen next packet come same process is repeated...
Disadvantage
Its is slow process ..becoz he wil luk into each packet ....

Fast switching
it wil so de same but only to first packet and den store the info in cache...so process become fast

Disadvantage
Perpacket load sharing...not possible

CEF(cisco express forwarding) LIFE SAVER(LOL)
it wil not even luk into first packet it wil bulid FIB(forward info base)..and with the help of FIB it wil build ADJ table and store that in cache...

disadvantage
more memory is needed....
cisco proprietary

MPLS(industry standard)
same as CEF but its industary standarad


hope this helps u out.....

Thanks bro very usefull!!

[Big Evil]

Thanks bro very usefull!!
Indeed. Top marks.

[xpaslan]

process switching
its bascically the process of luking into each packet see its source table and destination ip den send arp gets other mac adress and then forward the packet...
so wen next packet come same process is repeated...
Disadvantage
Its is slow process ..becoz he wil luk into each packet ....

Fast switching
it wil so de same but only to first packet and den store the info in cache...so process become fast

Disadvantage
Perpacket load sharing...not possible

CEF(cisco express forwarding) LIFE SAVER(LOL)
it wil not even luk into first packet it wil bulid FIB(forward info base)..and with the help of FIB it wil build ADJ table and store that in cache...

disadvantage
more memory is needed....
cisco proprietary

MPLS(industry standard)
same as CEF but its industary standarad


hope this helps u out.....
Lol, you have answered it well.
Thanks cos i need the info too