- In a URL, we can specify either hostname or IP address. Similarly, while we can specify port number, can we specify service name instead of port number ? If we can't, how can we specify service name when it is needed (e.g. in case that we don't remember port number for a service)?
Can we specify transport protocol in URL? If we can't specify transport protocol in a URL, how can we specify transport protocol when it is needed? The need to do that is that a service name may correspond to two transport protocols, for example, in
/etc/services
http 80/tcp # Hypertext Transfer Protocol http 80/udp ssh 22/tcp # Secure Shell ssh 22/udp telnet 23/tcp # Telnet telnet 23/udp smtp 25/tcp # Simple Mail Transfer Protocol smtp 25/udp
Thanks.