# Routing protocols in ISP WAN link?



## escape (May 5, 2016)

Is it important to add RIP, BGP or OSPF to the WAN link to ISP if only one public IP is used?

Is the routing for the ISP -only or do I have to add the address with a routing protocol? How can I determine what routing protocol the ISP has used? 

What is the best router software and how to configure the WAN link?

/escape


----------



## SirDice (May 9, 2016)

escape said:


> Is it important to add RIP, BGP or OSPF to the WAN link to ISP if only one public IP is used?


No, you don't need any of them.



> Is the routing for the ISP -only or do I have to add the address with a routing protocol?


You just set a default gateway, nothing more.



> How can I determine what routing protocol the ISP has used?


You don't.



> What is the best router software and how to configure the WAN link?


The same way as any other interface.


----------



## kpa (May 9, 2016)

You will need those routing protocols only if you're an ISP yourself or your ISP brings you multiple subnets with multiple upstream links and the complexity of the set up is too much for static routing. In the case of just one public IP there is nothing to do to "route", your system(s) just pass their data packets to their closest upstream router according to the "default gateway" entry in their routing table.


----------



## escape (May 11, 2016)

Yes. Using the NAT (network address translation) allows IP-networking with private addresses and the default route is enough to start. I'm still remembering some old practical advice, that it is good if the IP is advertised. I know the ISP is not known to implement the routing very well and it is good to advertise the IP anyway, to prevent others to use the same IP elsewhere or at the ISP:s network. This way my traffic is not routed through someone else's (users) router at the ISP and analyzed and the man in the middle attack is not as easy as without the advertising.

The ISP has some kind of instructions to use routing protocols for larger customers. These are different what I have get. I have get no instructions.

I think I had something to say here. It is cynical to just deny everything. Servers are not routers.

escape


----------



## gkontos (May 12, 2016)

You can not advertise a /32 that does not even belong to you.


----------

