Did you make a esofties context in extensions.conf? It needs to look something like this:
[esofties] exten => 200,1,Dial(SIP/200) exten => 201,1,Dial(SIP/201)
What will you eventually be asterisk for? If it will be for a business, you are going to want to reconsider the names of your peers. The names of the peers should not be the same as the extension number you want to assign to them. It keeps potential intruders from guessing peers names.