3: T
he x
Sw
itc
h i
n d
ep
th •
7
gress statistics refers to packets entering the switch
through the port. Egress statistics refer to packets leav-
ing the switch through the port. The page also identifies
the different size of packets passing through the switch
in the Histogram Statistics Counters.
Other statistic readouts are provided for your infor-
mation, as follows:
• GoodOctet – represents good data. An octet refers to
8 bits. Generally octet and byte are synonyms, but
some platforms in the past may have used byte to re-
fer to a different storage amount. To avoid ambiguity,
the term octet is used.
• Bad Octet – counter of bad data. Octet refers to 8 bits.
• Unicast – Transmission of data from one to one. The
counter indicates the amount of packets which are
unicast transmission messages.
• Broadcast – Transmission of data from one to all.
The counter indicates the amount of packets which
are broadcast transmission messages.
• Multicast – Transmission of data from one to many
— the basis of Livewire audio. The counter indicates
the amount of packets which are multicast packets.
• Pause – The counter shows the amount of Pause
frames as defined by the IEEE 802.3x standard. This
is a form of flow control allowing overwhelmed net-
work ends to halt data transmission.
• Undersize - The number of packets received that
were less than 64 octets long but were otherwise well
formed.
• Fragments – The number of packets received that
were less than 64 octets in length and had either a
bad Frame Check Sequence with an integral number
of octets (FCS Error) or a bad FCS with a non-inte-
gral number of octets (Alignment Error).
• Oversize – The number of packets received that were
longer than 1518 octets but were otherwise well
formed.
• Jabber – The number of packets received that were
longer than 1518 octets, and had either a bad Frame
Check Sequence with an integral number of octets
(FCS Error) or a bad FCS with a non-integral number
of octets (Alignment Error).
• RxErr – Error in received packets.
• FCSErr – Frame Check Sequence errors indicate cor-
rupted data on transmission.
• Deferred – Counter increments when a frame is to be
sent but the carrier is found to be busy. Typically an
issue only with half-duplex connections.
• Collisions - The result of two or more devices trans-
mitting at the same time on the same segment, pro-
ducing a garbled transmission. Collisions typically
are not an issue with full-duplex switched networks.
• InDiscards – Counter of packets received that are
tagged for a VLAN that the port is not associated
with, and so are dropped.
• InFiltered – Ingress packets being filtered.
• OutFiltered – Egress packets being filtered.
• <65 - 1024> – counters of different sized packets that
travel in and out of the switch.
IGMP Snooping
IGMP Snooping link provides information about the
switch’s snooping activity. In snooping, the switch is
able to determine which ports have requested a multi-
cast group and also determine how many groups have
been requested (Multicast Group Count). The page will
also identify the source of IGMP query messages and on
which port these messages are arriving.
The IGMP Snooping Table identifies the various
groups within the switch and which ports have made re-
quests for these groups. In cases where the group is one
that is used by Livewire, it will be identified by its sim-
pler Livewire Channel number or administrative func-
tion. In some cases you may see groups that are listed
which have no Livewire Channel. Some devices on the
network may request other multicast streams which are
used by other standards. Some examples:
224.0.0.107 - PTP
224.0.0.251 - mDNS
224.0.0.252 - LLMNR
...and a large list of others which can be found by
doing an Internet search on multicast addresses.
The IGMP snooping table will display all of the mul-
ticast request that have been made by devices connected
to the xSwitch.
©2013 Axia Audio
