What is the best routing protocol can be used on cisco devices?

it depends on the situation you have some times we need to use EIGRP because it has the lower AD (90) but it's used only in CISCo devices , We can use OSPF ( AD =110) but it can used in non cisco devices and so on ...

cisco routers support many routing prtocols  (both the interior and exterior gateway routing protocols)

-in the interioe gateway  routing the very powerful protocols are OSPF and EIGRP .

depending on your network devices ,if they are all cisco devices the best choice is to deploy the EIGRP(which is cisco proprietary protocol), else use the OSPF (which is open source routing protocol) that can be configured on both cisco and non cisco routers.

ghenimi,

best regards.

RIP , EIGRB , OSPF , BGP

on cisco device EIGRP 

as my freinds said it depends on ur requirements for example if u have cisco devices use eigrp better otherwise use ospf 

All protocols are good, RIPv2, OSPF, BGP, ISIS depending on the need and complexity of the problem.

It depends upon the requirement of the organisation. for example if the users are using phones like blacberry, iphone for connectivity on the network bettter go for EIGRP since it support multiple protocol and it is a very fast convergence protocol and morever it consumes less CPU resources unlike OSPF.

Depending on the role of the router within the network and how you want it to be setuped. Most common and best protocol for me are OSPF, BGP, EIGRP. The said protocol use is more direct or best routing possible for data transmission.

It depends on the design and objective of the network, RIP V2 which is widely and commonly used. EIGRP are commonly used now a days specially for big networks.

The routing protocol we use really depends on how our network is configured and what the future plans are. If we plan on having Cisco everything, we would have no problem using EIGRP.