outbound traffic = Upload while the inbound traffic means download?

[Ibrahim Jamil]

Hi Experts

in BGP , is the outbound traffic means Upload so it requires LOCAL_PREF?

             is the inbound traffic mean download so it requires AS_PATH?

thanks

ibrahim.jamil

[John Blakley]

Jamil,

Correct. Local_pref affects outbound traffic within an AS and the AS_Path prepending will affect inbound traffic. Using prepending, you can make a router less preferred over another.

HTH,

John

[Ibrahim Jamil]

Hi John

thnaks for ur reply

so

outbound traffic means Upload while inbound traffic mean download am i right ,

i have been asked a BGP Questions during interview like! what attribute in BGP used for download? not like which arributes infulence inbound traffic flow , y know the change of  the qustions confused me

Frankly speaking i told him AS-PATH with undestanding the questions

thanks

jamil

[John Blakley]

Well, that's a bad question actually. Inbound traffic could be considered download, but think of public FTP sites that allow uploads. If you're hosting an FTP site that allows upload, it's not considered a "download" from your perspective. It's better to think of download (inbound) as something coming into your AS and upload (outbound) as coming out of your AS.

The MED attribute can also affect inbound traffic into your AS. When you send MED to the provider, it will compare and pick this if other attributes are the same. The provider will send to the lowest metric advertised if you have 2 routers in the same AS sending to the same provider. You can also set MED inbound for routes to influence outbound traffic as well, but generally you'll want to use something higher up in the list (weight, local pref).

Weight attribute can also affect outbound traffic and is a Cisco specific attribute.

When you get interview questions like that, you should throw them for a loop and talk about all of the different directions that you know about

[Kishore Chennupati]

Jamil,

When they ask you questions like that and if its not clear ask them to clarufy. nothing wrong in that. When they asked you bgp attribute for download. you can ask whether they are talking about traffic coming into the AS etc. or is it from the ISP perspective or thu customer perspective as well.  Sometimes these interviewers ask questions which make no sense. They just want to dik around..

oh well hope you get the job mate and oh John has answered your questinos anyway

Kishore

[Ibrahim Jamil]

thanks John , thanks Kishore