User's Manual

Table Of Contents
CHAPTER 4
REPEATING FEATURES
Revised: 24 Jan 14 4-3 EST P/N AA107-195CM
RAPID SPANNING TREE PROTOCOL (RSTP)
The ESTeem Model 195C/M uses Rapid Spanning Tree Protocol (RSTP - IEEE 802.1d) to determine the radio routing structure of
the wireless network. This RSTP functions the same as standard Spanning Tree Protocol (STP) listed below, but the network
recovery is three times faster. If the 195C/M is used in a network that has any older STP only modems, the entire network will be
STP.
SPANNING TREE PROTOCOL (STP)
The ESTeem Model 195C/M uses standard Ethernet Spanning Tree Protocol (STP) or Rapid Spanning Tree Protocol (RSTP) to
determine the radio routing structure of the wireless network. The primary purpose of STP/RSTP is to make sure that “network
loops” are not created. A network loop is having two communication paths to the same destination where the remote device would
receive the same data multiple times. If there were no way to control the data flow, this data would be constantly passed around
this loop causing a “packet storm” that would shut down the entire network. The Spanning Tree Protocol will block all these
redundant links.
Figure 3: Programming Example #1 Diagram
Th
e STP operation begins by determining which Ethernet device on the network will be the Root Bridge. All Ethernet networks
have a Root Bridge that is selected by the lowest MAC address. All path costs are evaluated against this Root Bridge device to