it would be very useful to add this info (servicename and interface from where is connect user) in show sessions :
ifname | uplinkif | servicename | username | calling-sid | ip | rate-limit | type | comp | state | uptime
--------+----------+----------+-------------------+-----------+---------------+-------+------+--------+----------
ppp0 | vlan321 | testservice1 | testuser | 1e:45:a7:fe:40:06 | 10.26.0.1 | 102400/102400 | pppoe | | active | 00:03:09
ppp1 | vlan123 | testservice2 | testuser1 | 1e:45:a7:fe:40:06 | 10.26.0.1 | 102400/102400 | pppoe | | active | 00:04:09
ppp2 | vlan321 | testservice1 | testuser3 | 1e:45:a7:fe:40:06 | 10.26.0.1 | 102400/102400 | pppoe | | active | 00:06:09
and to easy search and show only user by this interface or servicename
show sessions match servicename (testservice1):
ifname | uplinkif | servicename | username | calling-sid | ip | rate-limit | type | comp | state | uptime
--------+----------+----------+-------------------+-----------+---------------+-------+------+--------+----------
ppp0 | vlan321 | testservice1 | testuser | 1e:45:a7:fe:40:06 | 10.26.0.1 | 102400/102400 | pppoe | | active | 00:03:09
ppp2 | vlan321 | testservice1 | testuser3 | 1e:45:a7:fe:40:06 | 10.26.0.1 | 102400/102400 | pppoe | | active | 00:06:09
or by interface (vlan123):
ifname | uplinkif | servicename | username | calling-sid | ip | rate-limit | type | comp | state | uptime
--------+----------+----------+-------------------+-----------+---------------+-------+------+--------+----------
ppp1 | vlan123 | testservice2 | testuser1 | 1e:45:a7:fe:40:06 | 10.26.0.1 | 102400/102400 | pppoe | | active | 00:04:09