Chapter 32: Packet Throttling
STANDARD Revision 1.0
C4® CMTS Release 8.3 User Guide
© 2016 ARRIS Enterprises LLC. All Rights Reserved.
933
IGMP packets passed: 3085 packets
IGMP packets dropped: 0 packets
SNMP packets passed: 576588 packets
SNMP packets dropped: 1 packets
TFTP packets passed: 29405 packets
TFTP packets dropped: 0 packets
IS-IS packets passed: 42759 packets
IS-IS packets dropped: 0 packets
IPv6 ND packets passed: 340993 packets
IPv6 ND packets dropped: 0 packets
IPv6 DHCP packets passed: 1105693 packets
IPv6 DHCP packets dropped: 0 packets
IPv6 ICMP packets passed: 3 packets
IPv6 ICMP packets dropped: 0 packets
IPv6 MLD packets passed: 0 packets
IPv6 MLD packets dropped: 0 packets
IPv6 TFTP packets passed: 4260 packets
IPv6 TFTP packets dropped: 0 packets
BGP packets passed: 5133 packets
BGP packets dropped: 0 packets
PIM packets passed: 2532 packets
PIM packets dropped: 0 packets
LACP packets passed: 0 packets
LACP packets dropped: 0 packets
SNMP-CM packets passed: 100360 packets
SNMP-CM packets dropped: 0 packets
COPS packets passed: 74828 packets
COPS packets dropped: 0 packets
TELNET packets passed: 78065 packets
TELNET packets dropped: 0 packets
RSM other packets passed: 0 packets
RSM other packets dropped: 0 packets
SCM global packets passed: 0 packets
SCM global packets dropped: 0 packets
Upstream Cable Protocol Throttling
Upstream channels on the cable or subscriber side of the network can be inundated by DHCP and ARP and IGMP packets
coming from modems and Customer-Premise Equipment (CPE). These DHCP or ARP requests may come from malicious
users, viruses, spyware, or faulty equipment.
The C4/c CMTS uses three leaky buckets to throttle packets. One bucket collectively throttles al IPv4 ARP and IPv6 ND type
packets, and a second bucket throttles all IPv4 and IPv6 DHCP packets, and a third throttles IGMP packets.
The following types of packets are all considered ARP/ND type packets, and are collectively throttled using one leaky
bucket:
ARP Request packets
ARP Reply packets
ND Neighbor Solicitation packets
ND Neighbor Advertisement packets