Why?

[#1]

My broadband and connection has been really good the last few months and for some reason my connection as been erratic the last few days,this started when my connection tried to unidentified  network and I am unable to know why this as happens I have not altered anything.

[#2]

That sounds as though it is your wireless connection to the router which is playing up.
Is this correct

[#3]

Oldjim beat me too it.  I had already written:
"Unidentified network" messages are usually associated with a wireless problem i.e. between your device and your router.  Not really anything to do with the broadband connection between your router and the telephone exchange.

[#4]

Sounds like your device is trying to connect to a neighbouring wifi network!
Network Properties will reveal the name of the network it is trying to connect to.

[#5]

This is correct in what you said regarding my connection from my wireless to my router,I rebooted my router a week ago and I did not have this problem I also noticed that sometimes I   have a exclamation mark on my wifi logo,is there a solution to this although it is not such a big problem but it would be nice to get to the bottom of this.

[#6]

Usually turning the wireless off then on again (or otherwise disconnecting then reconnecting) solves this issue, please let us know if that doesn't help though.