USBLAN for Windows - RNDIS Protocol Support

Belcarra is pleased to announce the addition of the RNDIS protocol to their USBLAN for Windows Network over USB solution (http://usblan.belcarra.com/),

Belcarra’s USB Class Driver is a suite of products which enables networking over the USB link. Belcarra’s RNDIS implementation provides several USBLAN features including faster data transfer abilities. The addition of RNDIS gives Belcarra's USBLAN for Windows the most complete set of USB networking protocols available in a single driver product.

http://www.prweb.com/releases/2012/8/prweb9769681.htm

Contact us to receive your evaluation copy of the  USBLAN 2.4.4 release.

Virtual Driver for USB Network Devices

USBLAN for Mac OS/X

Belcarra’s new Virtual Driver for Networked USB devices greatly improves the end user experience for interfacing smart devices to the Mac OS/X desktop.

Traditional solutions create a network interface for each attached device requiring the user to find and then configure a network service for the interface with the correct operating parameters (IP address etc.)

Belcarra’s solution features a Virtual Network Interface that is created when the system is started. This interface can be configured to a static IP address or simply default to use the normal DHCP configuration.

USBLAN 2.4.1 Available

USBLAN 2.4.0 release provided support for CDC-NCM and Microsoft NDIS 6.

USBLAN 2.4.1 now adds support for the Microsoft RNDIS protocol.

OEM's with with WinCE, embedded Linux or other devices configured to use RNDIS can now simply take advantage of USBLAN's many networking features such as:

• DHCP Service – DHCP service is not need on target or Windows, USBLAN's built in DHCP server option can be used to co-ordinate and assign address of both the host and device network interfaces 
• Composite function – the USBLAN driver is fully compatible with the Windows USB composite function support 
• WHQL – drivers are fully compatible with Microsoft Windows Hardware Quality Labs (WHQL) tests and procedures 
• Multiple devices can be connected allowing peer to peer networking and to the Windows desktop.

An evaluation version and OEM manual are freely available

Belcarra EEM Configuration Extension Descriptor

The CDC-EEM protocol is capable of aggregating multiple network datagrams into a single Bulk Data transfer.

The standard does not implement a mechanism to allow the host and device to determine an appropriate size for Bulk transfers. While implementing EEM without this information is possible, it complicates the implementation. If the Host and Device know what the capabilities of the other end are (WRT to transfer size especially) then the driver implementations can be significantly simpler and easier to implement.

Multiple Frame Support

Networking over USB protocols can support network frame aggregation. This allows for multiple network frames to be transferred in a single Bulk Data transfer.

USB Bulk Data transfers have overheads. Both at the bus level where individual transfers must be terminated with a short data packet. And at the OS level where the USB controller drivers must setup and tear down each transfer. And finally in the communication between the protocol driver (class driver on host systems and matching function driver on devices) and the low level controller drivers. These add latency to the time it takes for each transfer to take place.

Aggregating multiple network frames into a single Bulk Data transfer allows the overheads and associated latencies to be absorbed across multiple network frames.

Care must be taken in the use of this feature though. Additional latency is induced as the entire Bulk Transfer must be received before any of the network frames it contains can be forwarded. This places a bound on effective number of frames that should be aggregated. The actual number is best determined by using simple heuristics at runtime to ensure that the use of available bandwidth is optimized with only minimal latency added.

Effective multi-frame support can provide close to 100% improvement in throughput.

See also: Networking over USB Protocol Comparison

Evaluation Version 2.4 USBLAN from Windows Update

The new version of Belcarra's USB Class Driver for Windows is available through the Microsoft DDC.  To use the USBLAN 2.4 evaluation driver your device will need to offer Vendor ID 0x15ec (Belcarra) and our Demo Product ID 0xd041. Ensure that your Windows system is connected to the Internet, plug your device in and let Windows search Windows Update.  The protocol (CDC-ECM, CDC-EEM, CDC-NCM and RNDIS) is automatically detected.

The INF file of the USBLAN evaluation driver creates global variables in the registry using Service name BelcarraDemoUSBLAN (see Section 5.2). These parameters can be modified later using Regedit. Alternatively, common operations, like enable or disable DHCP, can be performed by installing the appropriately named INF file in a supplementary package of INF files (available on request). For example, to enable the DHCP feature do the following
• right-click on the file dhcpd-enable.inf in Windows Explorer
• select the method Install
N.B. the evaluation USBLAN driver is not the debug version of the driver. If you need to debug your USB device contact support@belcarra.com for a debug (CHK) version of the evaluation driver.

This evaluation version will run for 30 minutes at a time. It must be re-plugged to continue use.