URL redirects; for general purpose use, which is better: server-side or client-side?

Question

Take a very simple case as an example, say I have this URL:

http://www.example.com/65167.html

and I wish to serve that content under:

http://www.example.com/about

UPDATE: Note that the 'bad' URL is the canonical one (it's produced by a CMS which uses it internally for linking), so "/about" is just a way of polishing it.

I have two broad options: a server-side redirect or a client-side one. I always thought that server-side would be preferable since it's more efficient, i.e. HTTP traffic is approximately halved. However, SEO techniques tend to favour a single URL for a resource, thus client-side is to be preferred.

How do you resolve this conflict, and are there other factors I've omitted?

Answer 1

Apache HTTPD's mod_rewrite can leave a browser showing a SEO-friendly URL in its location bar while redirecting to a numeric URL on the server:

RewriteEngine on
RewriteRule ^/about$ /65167.html [L]

Answer 2

I'm pretty sure Google understands 301 Moved Permanently.

Answer 3

A 301 is the wrong approach for this problem if you're redirecting from /about to /65167.html. Your CMS will only understand the 65167.html request but a 301 is basically telling Google that /about no longer exists and to index the 65167.html page.

Ignacio is correct. You need to implement either mod_rewrite or something similar depending on your platform and hide the CMS assuming that you can actually re-write all your CMS generated links to something more friendly.

A client side redirect is probably too complex to implement and a server side redirect will cause two requests to the server.