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Basic Configuration

Overview

The VDAC-ONE card requires basic card configuration of spans and channels similar to the T-ONE card.

Refer to the API Reference for additional information on the API messages and TLVs mentioned hereafter.

API Messages

You can use the following API Messages to configure the VDAC-ONE card. Refer to the API Reference for details of each:

• ARP Cache Query (0x00FC)

• ARP Cache Report (0x00FB)

• IP Address Configure (0x00E7)

• IP Address Query (0x00E6)

• Resource Attribute Configure (0x00E3)

• Resource Attribute Query (0x00E4)

• Route Control (0x00E8)

• Card Population Query (0x0007)

• Assign Span (0x00A8)

• Service State Configure (0x000A)

Configuration

Follow the steps below to configure the VDAC-ONE Card. The API messages involved appear in parenthesis.

1. Configure IP addresses, subnet masks, and gateway IP addresses (IP Address Configure 0x00E7).

• On a fully-populated VDAC-ONE card (with four VoIP modules) you assign five IP Addresses/Subnet Masks (one to the main board and one to each of the VoIP modules). See your IT/network administrator to ensure that you use the correct values for your network configuration.

2. Assign Logical Span IDs (Assign Span 0x00A8).

• Depending on your application and configuration, you can assign five spans of 32 channels each to the four VoIP modules.

3. Configure Call Control parameters with PPL Configure 0x00D7.

4. Bring spans in service with Service State Configure 0x000A.

5. Bring channels in service with Service State Configure 0x000A.

Configuring IP Address and Subnet Mask

The IP address is 32 bits. IP addresses and subnet masks can be assigned using the IP Address Configure message.

If the host sends an IP Address Configure message with an IP address and subnet mask that differ from the values stored in the Electronic Erasable Programmable Read Only Memory (EEPROM), the new values will overwrite the stored values.

If the host assigns the same IP address and subnet mask, the message is acknowledged and the card does not need to be reset, so the host can send the IP Address Configure message whenever it is necessary.

For the new IP address and subnet mask to take effect, you must reboot the card. You can perform this step by including the Engage IP TLV in the IP Address Configure message.

The subnet masks default to the values shown in the following table.

Table 2-1 Default Values

Class | IP Address | Subnet Mask
A | 1.0.0.0 - 127.0.0.0 | 0xFF.00.00.00
B | 128.0.0.0 - 191.0.0.0 | 0xFF.FF.00.00
C | 192.0.0.0 - 254.0.0.0 | 0xFF.FF.FF.00

Assigning Dynamic IP Addresses

You can dynamically assign an IP address to a VoIP module without affecting the other modules on the VDAC-ONE card. You configure the IP address on a module by using the IP Address Configure message, with the IP Address/Subnet Mask TLV (0x01). You must include one of the following TLVs in the message as well:

• Engage IP TLV (0x02)

• Reset IP TLV (0x03)

Re-Assigning an IP Address

When IP addresses are re-assigned, the TCP/IP stack must be re-initialized. To properly re-initialize the stack, you must reboot the board or module using one of the following TLVs in the IP Address Configure message:

• Engage IP TLV (0x02)

• Reset IP TLV (0x03)

Gateway IP Address

You can assign Gateway IP addresses to the VDAC-ONE card, to the VoIP modules or both. When you use the IP Address Configure message to assign a Gateway IP address, you must include in the message the corresponding IP address and subnet mask.

Ethernet Link Redundancy

If you configure redundancy for the Ethernet links on the VDAC-ONE card, the standby Ethernet port becomes active automatically if the previously active link fails. Ethernet Link Redundancy is disabled by default.

To configure Ethernet Link Redundancy:

1. Connect the lower Ethernet port on the VDAC-ONE card to an Ethernet switch.

2. Enable Ethernet Link Redundancy on the VDAC-ONE card by using the Ethernet Link Redundancy (0x09) TLV in the IP Address Configure message.

To manually activate an Ethernet port, send the IP Address Configure message with the Activate Ethernet Port TLV (0x0A).

To query the state of Ethernet Link Redundancy, use the IP Address Query message.

Do not enable Ethernet Link Redundancy unless there are IP connections to both the upper and lower Ethernet ports on the VDAC-ONE card.

Flexible RTCP and T.38 Port Selection

You can choose any port number for RTCP and T.38 connections. By using the RTCP or T.38 port TLVs, the host explicitly specifies port values at one of the following three points:

• Before the call is connected (with the Resource Attribute Configure 0x00E3 message and the IP Address AIB)

• During call setup (with the Route Control 0x00E8 and Outseize Control 0x002C messages)

• During an active call (with the Resource Attribute Configure 0x00E3 message and the Span/Channel AIB)

This flexible port selection scheme reduces or eliminates interoperability issues with other gateways and IP-enabled switches. It also aligns with the requirements set forth by the ITU-T H.323 Annex D standards, as well as other protocols such as SIP.

Considerations

The VDAC-ONE card does not automatically select the T.38 ports. Instead, the host must select the source and destination T.38 ports. The VDAC-ONE card is fax-aware whenever Fax Relay Mode is enabled. The VDAC-ONE card detects the CED (Called Station ID) tone from the PSTN or T.38 packets from an IP network. The card then alerts the host with a PPL Event of Fax Start. The channel then transitions from voice to fax mode and starts generating only T.38 packets. At this point, the host must select the T.38 port as quickly as possible. Otherwise, the VDAC-ONE card discards any T.38 packets. The fax machines at each endpoint will then give up because they do not receive an appropriate response, and the fax transmission fails.

DTMF over IP Considerations

Refer to DTMF over IP Considerations .

VDAC-ONE Card over the Exnet® Ring

The VDAC-ONE card over the Exnet® ring is similar to any other resource over the ring. Spans are assigned on the VDAC-ONE card and this span information is shared among all nodes. When the host sends a message to connect to a VDAC-ONE card span/channel on a remote node, the system makes the connection to the remote node.

You must configure the ring for four packets (not three as normal).

Important! Ring Timing is not supported on nodes that contain VDAC-ONE cards. Use Loop Timing from a non-VDAC span or an external clock source.

Address Resolution Protocol (ARP)

The VDAC-ONE card supports the Address Resolution Protocol (ARP) of TCP/IP, which is used to obtain the physical address (Ethernet address) of an endpoint when only the logical address (IP Address) is known.

The CSP broadcasts an ARP Request message to the network with the known IP address. The corresponding endpoint responds with its Ethernet address and the connection is made.

The VDAC-ONE card drops all incoming the VDP packets and generates a single ARP request per second for each VDAC-ONE channel until the Destination Hardware Address (MAC address) is received.

ARP Cache Table

Each module on the VDAC-ONE card maintains an ARP Cache Table containing the IP Address and Ethernet address of remote endpoints. These tables allow connections to be made to the remote endpoint without sending the ARP Request message each time. An ARP Cache Table can contain a maximum of 40 entries.

You can query the content of a module’s ARP Cache Table by using the ARP Cache Query message. The ARP Cache Table information is sent to the host in one or more ARP Cache Report messages.

ARP Cache Aging

With the ARP Cache Aging feature, entries in the ARP cache are deleted after a preset interval. Each entry in the ARP cache has an associated time-to-live. The ARP Cache Aging timer is set to five minutes. The ARP Cache manager continually increments the time-to-live field, and discards the entry when the value reaches the aging timer value. Entries are removed based solely upon the time-to-live value, and not upon the frequency that the entry was used.

ARP Cache Query

This feature allows the host to use the ARP Cache Query message to query the ARP cache of any XoIP module. The CSP responds with one or more ARP Cache Report messages that contain all existing ARP cache entries.

ARP Cache Flushing

You can manually remove entries from an ARP Cache Entry Table by using the Flush ARP Cache Entry TLV in the ARP Cache Query message.

Internet Control Message Protocol (ICMP) Message

The VDAC-ONE card supports the Internet Control Message Protocol (ICMP), which reports errors related to IP packet processing. If the VDAC-ONE card attempts to connect to a remote endpoint and receives the ICMP message Destination Unreachable, it flushes the entry for that IP address from the ARP Cache Table, and sends an ARP Request message to obtain a new Ethernet address for the entry. When the VDAC-ONE card receives the new Ethernet address, the connection is made and the ARP Cache Table is updated. This process occurs without host intervention or notification.

The VDAC-ONE can generate the following ICMP message types:

• Destination Unreachable

• Echo Reply (Ping Reply)

The VDAC-ONE can process the following incoming ICMP messages:

• Destination Unreachable

• Echo Reply (Ping Reply)

Internet Protocol. Part of the TCP/IP family of protocols used to route messages and tracks the addresses of nodes.
A 32-bit address, used in IP routing, which includes a Network address identifier assigned by a central authority and a Host ID (an end station identifier assigned by a LAN administrator).
Range of channels provided by T1 or E1 transmission service. A physical span is a group of channels taking up a single physical wire. A logical span is a group of channels taking up less than a single logical wire, or carried over more than one physical wire.
The condition of a component at a given instant. The current "context" of a PPL object, such as Idle, Seizing, Answered. In PPL files, a State is represented by a circle.
Voice Data Access Concentrator Card. Performs two-way conversion between circuit-switched data and packet-switched Ethernet data required by packetized voice applications such as VoIP.
Voice over Internet Protocol. The delivery of voice information in digital form in discrete packets rather than in the traditional circuit-committed protocols of the public-switched telephone network (PSTN).
Setting up, monitoring, and tearing down calls.
See Programmable Protocol Language.
The bits of an Internet Protocol (IP) address used for a subnetwork.
Tag-Length-Value block. A standardized block that allows data to inserted in a standard way into API messages.
Transmission Control Protocol / Internet Protocol. A networking protocol that provides communication across interconnected networks.
A device that translates calls between an IP network and another network, typically the PSTN.
The protocol used in most local area PC networks. Typically, most Ethernet networks support data transmission speeds up to 10 Mbps, but 100 Mbps is also possible.
The point in the Excel platform where a DS0 connects to a network. Also known as a "socket."
Real-Time Transport Control Protocol.
See Address Information Block.
Outgoing call setup during real-time call processing on a specific channel.
International Telecommunications Union (UN)
ITU-T standard defines a set of call control, channel setup, and codec specifications for transmitting real-time voice and video over networks that do not offer guaranteed service or quality of service.
Session-Initiation Protocol. A signaling protocol used for establishing sessions in an IP network. A session could be a simple, two-way telephone call, or it could be a collaborative multi-media conference session.
Public Switched Telephone Network
A condition that, when met, drives a state machine from one state to another. A condition that drives a Component out of its current state by invoking an associated primitive.
More than one traffic type (voice, data, fax, or modem) over Internet Protocol.