User guide

Chapter 5: Technical Configuration
The Ethernet/IP Parameters fields are described in the tables and text passages below. Note that both
DiffServ parameters (Call Control PHB and VoIP Media PHB) must be set to zero if you enable Packet
Prioritization (802.1p). Nonzero DiffServ values negate the prioritization scheme.
Ethernet/IP Parameter Definitions (cont’d)
Field Name Values Description
Ethernet Parameters
Packet
Prioritization
(802.1p)
Y/N
Select to activate prioritization under 802.1p protocol (described
below).
.
Frame Type Type II, SNAP
Must be set to match network’s frame type. Default is
Type II.
802.1p A draft standard of the IEEE about data traffic prioritization on Ethernet networks. The
802.1p draft is an extension of the 802.1D bridging standard. 802.1D determines how
prioritization will operate within a MAC-layer bridge for any kind of media. The
802.1Q draft for virtual local-area-networks (VLANs) addresses the issue of
prioritization for Ethernet networks in particular.
802.1p enacts this Quality-of-Service feature using 3 bits. This 3-bit code allows data
switches to reorder packets based on priority level. The descriptors for the 8 priority
levels are given below.
802.1p PRIORITY LEVELS
LOWEST PRIORITY
1 – Background:
Bulk transfers and other activities permitted on the
network, but should not affect the use of network by other users
and applications.
2 – Spare:
An unused (spare) value of the user priority.
0 – Best Effort (default): Normal priority for ordinary LAN traffic.
3 – Excellent Effort:
The best effort type of service that an information services
organization would deliver to its most important customers.
Ethernet/IP Parameter Definitions (cont’d)
Field Name Values Description
Ethernet Parameters
802.1p (continued)
4 – Controlled Load: Important business applications subject to
some form of “Admission Control”, such as preplanning
of Network requirement, characterized by bandwidth
reservation per flow.
5 – Video:
Traffic characterized by
delay < 100 ms.
6 – Voice:
Traffic characterized by
delay < 10 ms.
7 - Network Control:
Traffic urgently needed to maintain and
support network infrastructure.
HIGHEST PRIORITY
Call Control
Priority
0-7, where 0 is
lowest priority
Sets the priority for signaling packets.
VoIP Media
Priority
0-7, where 0 is
lowest priority
Sets the priority for media packets.
Others (Priorities) 0-7, where 0 is
lowest priority
Sets the priority for SMTP, DNS, DHCP, and other
packet types.
VLAN ID 1 - 4094 The 802.1Q IEEE standard allows virtual LANs to
be defined within a network. This field identifies
each virtual LAN by number.
Multi-Tech Systems, Inc. TalkAnyTime User Guide 68