Gerdes PrimuX SIP 2 ISDN access device Wired — supports X.25, X.75, HDLC, V.110, ISO 8208, LAPD

Gerdes PrimuX SIP 2 is a wired ISDN access device and VoIP gateway designed to bridge legacy packet-switched and ISDN data links with modern SIP-based networks. The device supports a wide range of protocols — X.25, X.75, transparent modes, HDLC transparent, V.110, T.70 NL, T.90 NL, ISO 8208 and LAPD — enabling migration and interoperability for telephony and data transmission across ISDN and IP infrastructures.

Advantages

The Gerdes PrimuX SIP 2 provides protocol-level compatibility for legacy systems while presenting SIP connectivity for contemporary telephony and data environments. Its support for multiple encapsulation and link protocols allows seamless translation between ISDN interfaces and IP networks, reducing the need to redesign existing terminal equipment. The device's wired design focuses on stability and predictable latency for time-sensitive data and voice traffic.

Suitable for

• Integrating X.25-based packet services into SIP/VoIP environments
• Connecting ISDN LAPD signaling to SIP networks for telephony gateways
• Migrating legacy terminal equipment that uses HDLC or ISO 8208 to IP-based infrastructures
• Data transmission where V.110 or T.7x transparent modes are required
• Enterprises or service providers maintaining mixed ISDN and SIP deployments

When it may not be suitable

The PrimuX SIP 2 is tailored for wired ISDN and legacy protocol integration; it is not intended as a general-purpose enterprise SIP PBX or as a wireless access device. It does not replace modern SIP-native endpoints where no legacy conversion is required. For deployments that require extensive codec transcoding, advanced unified communications features, or large-scale call routing and management functions, a dedicated SIP platform may be more appropriate.

Key specifications

• Supported protocols: X.25, X.75, transparent modes, HDLC transparent, V.110, T.70 NL, T.90 NL, ISO 8208, LAPD
• Interface type: wired ISDN access and IP (SIP) gateway
• Primary use: protocol conversion between legacy data links/ISDN and SIP networks
• Traffic types: packet-switched data and telephony signaling

How to use

Install the Gerdes PrimuX SIP 2 in a network rack or a stable location with wired ISDN and IP connectivity. Connect the ISDN interface to your legacy network device or line and configure the IP side with SIP credentials and network settings according to your SIP provider or PBX. Select and enable the required protocol mode (for example X.25, V.110 or LAPD) in the device configuration and map logical channels or virtual circuits to SIP endpoints or routes. Verify link parameters such as framing, baud rates for V.110, and addressing to ensure correct encapsulation and routing. Monitor logs and statistics during initial operation to confirm stable translation between ISDN/data links and SIP sessions.

What to consider before purchase

• Confirm that the specific legacy protocols you use (X.25, V.110, ISO 8208, LAPD, etc.) are required and supported
• Verify physical interface compatibility with your ISDN lines and terminal equipment
• Assess network provisioning: SIP credentials, NAT traversal, and IP routing must be configured
• Consider whether you need advanced SIP features (transcoding, call routing) not provided by a protocol-conversion gateway

Usage recommendations

For reliable operation, place the device in a controlled environment with stable power and wired network connections. Before full migration, test individual protocol mappings and a subset of calls or data sessions to validate encapsulation settings and timing parameters. Keep firmware up to date and document configuration mappings between legacy logical channels and SIP endpoints to streamline troubleshooting and future maintenance.