User manual

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Cisco ONS 15310-CL and Cisco ONS 15310-MA Ethernet Card Software Feature and Configuration Guide R8.5
78-18133-01
Chapter 11 Configuring Quality of Service on the ML-Series Card
Understanding IP SLA
Depending on the specific IP SLAs operation, statistics of delay, packet loss, jitter, packet sequence,
connectivity, path, server response time, and download time are monitored within the Cisco device and
stored in both CLI and SNMP MIBs. The packets have configurable IP and application layer options
such as source and destination IP address, User Datagram Protocol (UDP)/TCP port numbers, a type of
service (ToS) byte (including Differentiated Services Code Point [DSCP] and IP Prefix bits), Virtual
Private Network (VPN) routing/forwarding instance (VRF), and URL web address.
IP SLAs uses generated traffic to measure network performance between two networking devices such
as routers. IP SLAs starts when the IP SLAs device sends a generated packet to the destination device.
After the destination device receives the packet, and depending on the type of IP SLAs operation, the
device will respond with time-stamp information for the source to make the calculation on performance
metrics. An IP SLAs operation is a network measurement to a destination in the network from the source
device using a specific protocol such as UDP for the operation.
Because IP SLA is accessible using SNMP, it also can be used in performance monitoring applications
for network management systems (NMSs) such as CiscoWorks2000 (CiscoWorks Blue) and the
Internetwork Performance Monitor (IPM). IP SLA notifications also can be enabled through Systems
Network Architecture (SNA) network management vector transport (NMVT) for applications such as
NetView.
For general IP SLA information, refer to the Cisco IOS IP Service Level Agreements technology page
at http://www.cisco.com/warp/public/732/Tech/nmp/ipsla. For information on configuring the Cisco IP
SLA feature, see the “Network Monitoring Using Cisco Service Assurance Agent” chapter of the Cisco
IOS Configuration Fundamentals Configuration Guide, Release 12.2. at:
http://www.cisco.com/en/US/products/sw/iosswrel/ps1835/products_configuration_guide_chapter0918
6a008030c773.html.
IP SLA on the ML-Series
The ML-Series card has a complete IP SLA Cisco IOS subsystem and offers all the normal features and
functions available in Cisco IOS Release 12.2S. It uses the standard IP SLA Cisco IOS CLI commands.
The SNMP support will be equivalent to the support provided in the IP SLA subsystem 12.2(S), which
is the rttMon MIB.
IP SLA Restrictions on the ML-Series
The ML-Series card supports only features in the Cisco IOS 12.2S branch. It does not support functions
available in future Cisco IOS versions, such as the IP SLA accuracy feature or the enhanced Cisco IOS
CLI support with updated IP SLA nomenclature.
Other restrictions are:
• Setting the CoS bits is supported, but set CoS bits are not honored when leaving or entering the CPU
when the sender or responder is an ONS 15454, ONS 15454 SDH, ONS 15310-CL, or ONS
15310-MA platform. Set CoS bits are honored in intermediate ONS nodes.
• On RPR, the direction of the data flow for the IP SLA packet might differ from the direction of
customer traffic.
• The system clock on the ML-Series card synchronizes with the clock on the TCC2/TCC2P card. Any
NTP server synchronization is done with the TCC2/TCC2P card clock and not with the ML-Series
card clock.