Paradyne BitStorm 2400, Руководство пользователя

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1. BitStorm 2400 Overview
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December 2002 2400-A2-GB20-10
Secure VLAN Mode
The BitStorm 2400 also extends a secure VLAN mode in the web interface for
port-to-port security. In this mode, Etherloop ports can only communicate talk with
the WAN side of the network.
When a VLAN is in secure mode, packets received on member ports are
redirected to the uplink port (25) and not switched to other members. Conversely,
when a VLAN is not in secure mode, the member ports share packets as in a
normal VLAN.
VLAN secure status can be toggled with an SNMP browser (or the web interface)
by setting the private->enterprises->wrs->tms->idb->garpMib->garpMIBObjects->
gDot1qVlanStaticSecureTable->gDot1qVlanStaticSecureEntry->gDot1qVlanStatic
SecureRowStatus object to active(1) (or the integer 1) or notInService(2) (or the
integer 2). However, you must create and delete static VLANs through the
standard VLAN mibs. This can be set up through the VLAN setting instructions
documented in the
StormTracker EMS 2.3 User’s Guide .
Multicast Overview
Multicast support is provided by the BitStorm 2400 to deal efficiently with IP
multicast packets received from sources from the GigE link or from a locally
connected source. The primary application of IP multicast traffic is to deliver
content to one or more users with a single IP stream.
IP multicasts are used for many popular applications including:
!
Stock Ticker and news feeds (Pointcast)
!
Video and Audio streaming (broadcast like services over the IP network – Real
Media)
!
Some ‘Near’ Video on Demand servers (e.g., movies that start every
15 minutes)
!
Voice over IP (VoIP) conference calling features
!
Multipoint conference applications (Net Meeting, PictureTel)
True video on demand and point-to-point VoIP applications will typically use
unicast mechanisms (not multicast) for traffic delivery. These applications require a
server to communicate directly with a unique subscriber and send packets as
needed to each subscriber. Hybrid systems also exist where content is distributed
on a schedule via IP multicast and then play out on demand under local control.
As with any class of applications, there are many ways in which the services may
be provided. The features as described in this document for implementation in the
BitStorm 2400 will provide support for IP multicast application using IGMP V1
and/or IGMP V2 protocols. Some applications will combine IP streaming with
VLAN and CoS/QoS techniques to deliver unique services.
Care must be taken in designing large-scale implementations to properly
characterize the nature and behavior of the application, network and end stations.