ZyXEL Communications P-660HN-51 - 29.3 The OAM Ping Test Screen

P-660HN-51 User’s Guide
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The following table describes the fields in this screen.
29.3 The OAM Ping Test Screen
Click Maintenance > Diagnostic > OAM Ping Test to open the screen shown next. Use this screen to
perform an OAM (Operation, Administration and Maintenance) F4 or F5 loopback test on a PVC. The
Zyxel Device sends an OAM F4 or F5 packet to the DSLAM or ATM switch and then returns it to the Zyxel
Device. The test result then displays in the text box.
ATM sets up virtual circuits over which end systems communicate. The terminology for virtual circuits is as
follows:
Figure 127 Virtual Circuit Topology
Think of a virtual path as a cable that contains a bundle of wires. The cable connects two points and
wires within the cable provide individual circuits between the two points. In an ATM cell header, a VPI
(Virtual Path Identifier) identifies a link formed by a virtual path; a VCI (Virtual Channel Identifier)
identifies a channel within a virtual path. A series of virtual paths make up a virtual circuit.
F4 cells operate at the virtual path (VP) level, while F5 cells operate at the virtual channel (VC) level. F4
cells use the same VPI as the user data cells on VP connections, but use different predefined VCI values.
F5 cells use the same VPI and VCI as the user data cells on the VC connections, and are distinguished
from data cells by a predefinded Payload Type Identifier (PTI) in the cell header. Both F4 flows and F5
flows are bidirectional and have two types.
• segment F4 flows (VCI=3)
• end-to-end F4 flows (VCI=4)
• segment F5 flows (PTI=100)
• end-to-end F5 flows (PTI=101)
Table 98 Maintenance > Diagnostic > Ping & TraceRoute & NsLookup
LABEL DESCRIPTION
URL or IP
Address
Type the IP address of a computer that you want to perform ping, traceroute, or
nslookup in order to test a connection.
Ping Click this to ping the IP address that you entered.
TraceRoute Click this button to perform the traceroute function. This determines the path a packet
takes to the specified computer.
Nslookup Click this button to perform a DNS lookup on the IP address of a computer you enter.
• Virtual Channel (VC) Logical connections between ATM devices
• Virtual Path (VP) A bundle of virtual channels
• Virtual Circuits A series of virtual paths between circuit end points
Virtual Path
Virtual Channel
Segment
ATM Switch
Virtual Circuit (End-to-End)