• United States
Neal Weinberg
Contributing writer, Foundry

WAN monitoring tools

Nov 11, 20033 mins

* The Reviewmeister takes a look at Visual UpTime from Visual Networks and N-Form from Adtran

The Reviewmeister wanted to get a better handle on WAN usage, so we recently tested out a slew of WAN monitoring tools. Let’s start with Visual UpTime from Visual Networks.

The success of Visual UpTime is based on its close relationship with its Analysis Service Elements (ASE) devices. The ASEs continually measure link availability and activity on a second-by-second basis for each data link connection identifier (DLCI), yet still used our network quite frugally to inform Visual UpTime of the network’s current status.

We found UpTime’s calculations of round-trip delays very accurate. Those calculations excluded router serialization and insertion delay, and thus gave us a precise measurement of network delay for each permanent virtual circuit (PVC).

We even found that for the sake of accuracy, we could exclude scheduled maintenance periods from Visual UpTime’s calculations of uptime and bandwidth utilization. UpTime used the data from the ASEs to clearly show us outages and traffic levels.

It also showed us several frame relay metrics, such as per-port and per-PVC throughput, overall utilization, by-protocol utilization, bursting above the committed information rate (CIR) and network congestion identified by the presence of frame relay internal throttling mechanism packets.

Visual UpTime excels at helping administrators maintain WAN link details, locate link problems and track link activity. Clearly its designers carefully and thoughtfully focused on administrator productivity as they built Visual UpTime’s responsive and intuitive user interface to fit the workflow and individual tasks within a large network operations center.

For example, the Network Configuration dialog is a central point for changing or adding networks, sites, access lines, ASEs and circuits. Visual UpTime’s ability to print a network configuration report that documented our work was icing on the cake. We never had to fumble around in the interface to locate the right window through which to update network details, troubleshoot a problem or produce (or schedule) the appropriate reports for our WAN links.

Moving onto our second product,  Adtran’s IQ 710 traffic-shaping DSU/CSUs and N-Form software allow you to not only monitor links for availability, but also identify application-specific traffic and prioritize that traffic during busy periods.

Adtran can identify more than 300 kinds of application-level network datastreams, including Citrix WinFrame, HTTP, AOL Instant Messenger and Napster messages. Both the IQ 710s and N-Form track and display the same frame relay metrics as Visual UpTime, although with not quite much fine detail. 

Adtran’s N-Form main administrative window distinguishes between user-oriented and server-oriented tasks. Selecting the Users tab in the administrative tool brought up windows in which we could create, change or delete users. The Servers tab similarly was a doorway into configuring N-Form’s default SNMP settings, network utilization thresholds, e-mail identities, event history log and network event notifications.

N-Form’s Network Manager interface displays a hierarchical tree of network segments that identifies devices by address, type and status. An administrator can attach comments to each device’s N-Form data to help make the tree’s entries more meaningful. Network Manager can discover and display non-Adtran devices, but the tree’s “type” column is relevant only for Adtran devices. The tree’s “status” column, whose information is only as recent as the last SNMP polling sweep, only shows either “offline” or whether an e-mail notification is associated with a specific device. N-Form’s Network Manager tree can be collapsed or expanded to help drill down to specific segments and devices.

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