network traffic encryption

[ric...@tortoise.demon.co.uk]

I want to encrypt database traffic to an MSSQL 2000 server.

At the server (Win 2003 server sp2), using the SQL Server Network
Utility, the only enabled protocol is TCP/IP. Force protocol
encryption is checked. The server does have a certificate, issued by
itself, although when I examine it in the Certificates MMC snapin,
it's invalid, having expired. Despite this, I am able to stop and
restart the SQL service, an operation I thought should fail given
these circumstances.

At the client (XP sp3), the machine has no Trusted Root CA certificate
corresponding to the server and yet I can sucessfully run queries
using Query Analyzer.

Examining the traffic with a packet capture tool, if encryption is
switched off at the server, I can see SQL commands and returned data
inside the packets. If encryption is switched on at the server, I
can't tell if the traffic is encrypted, but certainly it's no longer
obviously human readable inside the packets.

None of this works as I expect.

I thought the SQL service shouldn't start with force encryption
checked if the server cert is invalid.

If the traffic is encrypted, without the client trusting the cert on
the server, I don't see how it can decode the traffic, at least
without alerting me.

Could anyone advise?

Regards
Richard