3onedata IES716-2GS, User Manual, Page: 37 / 54

User manual
Page 37
Ring Ports in Ring Group 2, Network ID is 2. Ring Type is Chain; as shown in figure 6.6.16.
（
Figure 6.6.15
）
（
Figure 6.6.16
）
3. Use a wire to connect Port 1 and 2 of Device 107-109 in turn to make a chain. Use a wire to
connect Port 1 and 2 of Device 100-103 in turn to make a Single Ring, Then use a wire to connect
Port 2 of Device 107 and Port 1 of Device 109 to normal port of Device 102 and 103. Chain is
finished.
1. Port can not be trunking setting when it is already Ring port.
2. In the same single ring, identity must be consistent, otherwise it will not built a ring and can not communicate.
3. All ring ports in the VLAN settings must be TRUNK tagged VLAN member, otherwise can not communicate.
4. To form tangent ring or other complex rings, should pay attention to the ring identity whether is it consistent,
different single ring identification must be different.
6.6.3 RSTP
The first spanning tree protocol was invented in 1985 at the Digital Equipment Corporation by Radia
Perlman. In 1990, the IEEE published the first standard for the protocol as 802.1D,based on the
algorithm designed by Perlman. Subsequent versions were published in 1998 and 2004, incorporating
various extensions.
Although the purpose of a standard is to promote interworking of equipment from different vendors,
different implementations of a standard are not guaranteed to work, due for example to differences in
default timer settings. The IEEE encourages vendors to provide a "Protocol Implementation
Conformance Statement", declaring which capabilities and options have been implemented, to help
users determine whether different implementations will interwork correctly.
Also, the original Perlman-inspired Spanning Tree Protocol, called DEC STP, is not a standard and
differs from the IEEE version in message format as well as timer settings. Some bridges implement
both the IEEE and the DEC versions of the Spanning Tree Protocol, but their interworking can create
issues for the network administrator, as illustrated by the problem discussed in an on-line Cisco
document.
Rapid Spanning Tree Protocol
In 2001, the IEEE introduced Rapid Spanning Tree Protocol (RSTP) as 802.1w. RSTP provides
significantly faster spanning tree convergence after a topology change, introducing new convergence