PBX systems for IP telephony /
Sulkin, Allan.
PBX systems for IP telephony / Allan Sulkin. - New York : McGraw-Hill, c.2002. - viii, 487 p. : ill. ; 24 cm. - McGraw-Hill telecom professional .
Index : p. 469-487.
0071375686 9780071375689
Internet telephony.
Telephone--Private branch exchanges.
621.387 / SUL
PBX systems for IP telephony / Allan Sulkin. - New York : McGraw-Hill, c.2002. - viii, 487 p. : ill. ; 24 cm. - McGraw-Hill telecom professional .
Index : p. 469-487.
0071375686 9780071375689
Internet telephony.
Telephone--Private branch exchanges.
621.387 / SUL