Cisco 2950 - Manual (Page 2)

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Migrate to Gigabit Speeds in the LAN
Midmarket customers who have existing copper (Category 5,
UTP) wiring infrastructure in their buildings now have a truly
compelling solution to migrate to Gigabit speeds in their LANs.
The Catalyst 2950T-24 delivers two fixed 10/100/1000BaseT
(Gigabit-Ethernet-over-copper) uplink ports in addition to
24 10/100 ports for desktop connectivity. For a fractional
increment in price per port, midsized businesses can now
upgrade their LANs to higher-performance Gigabit Ethernet.
In conjunction with the new Catalyst 3550-12T multilayer
Gigabit Ethernet switch, the Catalyst 2950T-24 switch provides
an integrated Gigabit-Ethernet-over-copper solution for
midmarket customers who have outgrown their Fast Ethernet
backbones.
Sophisticated Quality of Service
The Catalyst 2950 Series delivers sophisticated LAN-edge
QoS, unmatched in its category of products in the industry. All
Catalyst 2950 switches support two modes of reclassification.
One mode—based on the IEEE 802.1p standard—honors the
class-of-service (CoS) value at the ingress point and assigns
the packet to the appropriate queue. In the second mode,
packets can be reclassified based on a default CoS value
assigned to the ingress port by the network administrator. In
the case of frames that arrive without a CoS value (such as
untagged frames), Catalyst 2950 switches support
classification based on a default CoS value per port assigned
by the network administrator.
Once the frames have been classified or reclassified using one
of the above modes, they are assigned to the appropriate queue
at the egress. Catalyst 2950 switches support four egress
queues, which allow the network administrator to be more
discriminating and granular in assigning priorities for the
various applications on the LAN traffic. Strict Priority
Scheduling configuration ensures time-sensitive applications
such as voice, always follow an expedited path through the
switch fabric. Weighted Round Robin (WRR) scheduling,
another significant enhancement, ensures that lower-priority
traffic receives attention without comprising the priority
settings administered by a network manager.
These features allow network administrators to prioritize
mission-critical, time-sensitive traffic, such as ERP (Oracle,
SAP, and so on), voice (IP telephony traffic), and CAD/CAM
over less time-sensitive applications such as FTP or e-mail
(SMTP).
Multicast Management via IGMP Snooping
The Internet Group Management Protocol (IGMP) Snooping
feature allows the switch to “listen in” on the IGMP
conversation between hosts and routers. When a switch hears
an IGMP join request from a host for a given multicast group,
the switch adds the host’s port number to the Group
Destination Address (GDA) list for that group. And, when the
switch hears an IGMP leave request, it removes the host’s port
from the Content Addressable Memory (CAM) table entry.
By supporting IGMP Snooping in hardware and configuration
of IGMP Snooping via the Cisco Cluster Management Suite,
Catalyst 2950 switches deliver outstanding performance and
ease of use in administering and managing multicast
applications on the LAN.
Cisco Cluster Management Suite
The Cisco Cluster Management Suite (CMS) is Web-based
software that is embedded in Catalyst 2950, 3550-12T, 3500
XL, 2900 XL, and 1900 switches. Through Cisco Switch
Clustering technology, users access CMS with any standard
Web browser to manage up to 16 interconnected Catalyst
2950, 3550-12T, 3500 XL, 2900 XL, and 1900 switches at
once—regardless of their geographic proximity—using a
single-IP address. CMS provides an integrated management
interface for all Cisco IOS functionality, firmware
management, and offers administrators a powerful graphical
user interface (GUI) tool to easily monitor and manage their
LANs.
CMS supports a broad range of standards-based connectivity
options and configurations to deliver levels of performance
that are scalable to meet customer requirements. Switch
Cluster connectivity options for Catalyst 2950 switches
include Ethernet, Fast Ethernet, Fast EtherChannel, Gigabit
Ethernet (1000BaseT), and Gigabit EtherChannel
connectivity. Because the technology is not limited by
proprietary stacking modules or stacking cables, CMS
expands the traditional cluster domain beyond a single wiring
closet and lets users mix and match interconnections to meet
specific management, performance, and cost requirements.