Magnum 6K25 Managed Fiber Switch | Installation and User Guide (04/06) |
of the available bandwidth to be used for valid information.
While other switching technologies (such as "cut-through" or "express") impose minimal frame latency, they will also permit bad frames to propagate out to the Ethernet segments connected. The "cut-through" technique permits collision fragment frames (which are a result of late collisions) to be forwarded which add to the network traffic. Since there is no way to filter frames with a bad CRC (the entire frame must be present in order for CRC to be calculated), the result of indiscriminate cut- through forwarding is greater traffic congestion, especially at peak activity. Since collisions and bad packets are more likely when traffic is heavy, the result of store-and- forward operation is that more bandwidth is available for good packets when the traffic load is greatest.
When the Magnum 6K25 Switch detects that its free buffer queue space is low, the Switch sends industry standard (full-duplex only) PAUSE packets out to the devices sending packets to cause “flow control”. This tells the sending devices to temporarily stop sending traffic, which allows a traffic catch-up to occur without dropping packets. Then, normal packet buffering and processing resumes. This flow-control sequence occurs in a small fraction of a second and is transparent to an observer.
Another feature implemented in Magnum 6K25 Switches is a collision-based flow- control mechanism (when operating at half-duplex only). When the Switch detects that its free buffer queue space is low, the Switch prevents more frames from entering by forcing a collision signal on all receiving half-duplex ports in order to stop incoming traffic.
2.2.11Managed Network Software ( MNS-6K ) for Magnum 6K25-Series
Magnum 6K25-Series’s come with licensed MNS-6K Firmware (Rel 3.2),
which allows to configure the Magnum 6Ks as a Managed Switch and other Software enabled features. For additional information about MNS-6K, see the Magnum 6K25- Series MNS Software User guide in pdf format, a separate document normally accessed via your web-browser, at ftp://ftp.garrettcom.com/
or FTP client program by ftp.GarrettCom.com using
user : m6kuser
password : m6kuser
All MNS-6K software information, including new releases and upgrades related to MNS- 6K software, can be accessed and download from GarrettCom’s FTP site.
Alternatively, for documentation and latest information, or needed
GarrettCom proprietary MIBs for SNMP-
www . GarrettCom . com
