????????
?? ??: configuration management(?? ??), fault management(?? ??),
...... Continuity Test(??? ???)? ??. ...... per-VLAN spanning tree plus(
PVST+) ...... TP4 Transport Protocol Class 4(?? ???? ??? 4)? ??. OSI
?? ...... VIP Versatile Interface Processor? ??. virtual address(?? ??)
network ...