We have an asterisk installation that's on a residential-grade DSL and its port number (as visible from the outside) keeps changing, every time it registers. fuser indicates that asterisk is only using port 4569 for IAX2 (as it should), but when it goes out over the Internet, the port number is reported as something in the 10000's and it changes every time. Obviously, this is a network issue of some type, but can anyone explain more precisely why this happens and how to stop it? We have some other installations that stay put on port 4569 like they're supposed to. Network issues aren't my area of expertise. Thanks.
On Mon, 2004-02-09 at 10:52, Matt Lawson wrote:> We have an asterisk installation that's on a residential-grade DSL and > its port number (as visible from the outside) keeps changing, every time > it registers. fuser indicates that asterisk is only using port 4569 for > IAX2 (as it should), but when it goes out over the Internet, the port > number is reported as something in the 10000's and it changes every time. > > Obviously, this is a network issue of some type, but can anyone explain > more precisely why this happens and how to stop it? We have some other > installations that stay put on port 4569 like they're supposed to. > Network issues aren't my area of expertise.Networking 101. Inbound services must stay on a specific port so as to be known. Outbound connections can start on any port not already taken as long as it connects to the proper known service on the other side. This is normal operation. Watch your web browser sometime as it connects from some random high port to remote port 80 every time. -- Steven Critchfield <critch@basesys.com>
Matt Lawson wrote:> We have an asterisk installation that's on a residential-grade DSL and > its port number (as visible from the outside) keeps changing, every > time it registers. fuser indicates that asterisk is only using port > 4569 for IAX2 (as it should), but when it goes out over the Internet, > the port number is reported as something in the 10000's and it changes > every time. > > Obviously, this is a network issue of some type, but can anyone > explain more precisely why this happens and how to stop it? We have > some other installations that stay put on port 4569 like they're > supposed to. Network issues aren't my area of expertise. > > Thanks. >My guess would be NAT.. NAT boxes typically use high port numbers to map the return path for the data.. each time your box is registering it is probably being allocated another port on the NAT.. Of course I could be wrong.. ;) Later..
<quote who="Matt Lawson">> We have an asterisk installation that's on a residential-grade DSL and > its port number (as visible from the outside) keeps changing, every time > it registers. fuser indicates that asterisk is only using port 4569 for > IAX2 (as it should), but when it goes out over the Internet, the port > number is reported as something in the 10000's and it changes every time. > > Obviously, this is a network issue of some type, but can anyone explain > more precisely why this happens and how to stop it? We have some other > installations that stay put on port 4569 like they're supposed to. > Network issues aren't my area of expertise. > > Thanks.You obviously have a "Broadband Router/NAT" device. This allows multiple machines to connect to the DSL line, using one IP address. I would have to say, it is a fact of life, for a network setup like that. It is a matter of keeping state for the NAT. -- END OF LINE -MCP