SIP2 Manager (ABCD Plugin)

The SIP2 protocol implementation in the ABCD system manages connections for devices that assist in process automation, such as self-checkout equipment and remote readers. The module establishes multiple socket connections between the ABCD system (SIP server) and client devices using established protocols like TCP/IP. Information is exchanged through strings of characters called messages, initiating with a "request" from the client followed by a "response" from the server.

🚀 Architecture and Security

This module adheres to the modern modular architecture of the ABCD system[cite: 15]:

• Directory Structure: The plugin is installed in the /htdocs/content/plugins/ directory, keeping it independent and capable of supporting ABCD updates[cite: 14, 15].
• Security: The PluginBridge class is used to provide secure access to essential paths and block direct unauthorized access[cite: 15].
• Routing: It uses a basic MVC pattern where index.php acts as the main entry point (Router)[cite: 15].
• Internationalization: Translations are handled via the LanguageManager class using .tab files inside the /lang/ directory[cite: 15].

📡 Supported SIP2 Messages

The module listens for connections on port 5060 by default and supports the following messages:

Pair	Message Name	Supported
09-10	Checkin	Yes
11-12	Checkout	Yes
17-18	Item Information	Yes
19-20	Item Status Update	Yes
23-24	Patron Status	Yes
35-36	End Session	Yes
97-96	Resend last message	Yes
99-98	SC-ACS Status	Yes
CRC	CRC control	Yes
AY	AY sequence number	Yes

Note: Messages for Block Patron, Hold, Patron Enable, Renew, Fee Paid, Patron Information, Renew All, and Login are currently not supported.

⚙️ Configuration

Configuration parameters define how the server interacts with the network and databases:

• Network: Parameters include the SIP server IP ($ip_sip_server), the listening port ($port_sip_server), and the maximum number of allowed connections ($max_clients).
• Timeouts and Retries: Configurable values for message retries ($maxretry), transaction retries ($retries_trasaction), and timeouts ($sip_timeout_sc).
• Database Field Mapping: Fields must be mapped for searching item titles ($campo_titulo), inventory identifiers ($campo_inventario), physical locations ($campo_ubicacion), and security types ($campo_tipo_seguridad).

🗄️ Database Requirements

For the protocol to function correctly, specific data lists and parameters must be present in the databases:

• Fines: A table must be created in the suspensions and fines database (field 40) to define fee types recognized by the client (e.g., 04 for overdue, 03 for damage).
• User Blocks: Field v200 in the suspml database can be used to identify when a client automatically blocks a user.
• Security Markers: An additional field should indicate the physical security type of the items, which is mapped in the $campo_tipo_seguridad parameter.

🛡️ Security Considerations

• Connections to the SIP port may also allow external telnet connections.
• It is highly recommended to manage these connections using a server firewall or network security configurations.
• Always specify the exact number of client machines that will connect using the $max_clients parameter so that no connections are left available for unauthorized access.