Sc1021 – 802.11 MAC

Sc1021 is a wireless 802.11e MAC 802.11a/b/g compatible. It is the single 802.11/802.11e MAC in the industry which supports full standard 802.11 DCF, PCF and 802.11e QoS HCCA/EDCA concurrent modes. It is also capable of full audio/video streaming.

It has been tested and independent verified by customers.

Sc1021 comes with APB/AHB /PCI system interface (with master DMA or slave capabilities) and standard 802.11g/802.11ab PHY interface.

It supports concurrent multiple PHY’s (PHYb/PHYa/PHYab/PHYg) for high end AP/HC applications.

Sc1021 is structured and designed to minimize the Host effort and to maximize the throughput (packets/sec) for video streaming. Maximum theoretical payload (IP packets) throughput. No latencies in clear or encrypted mode.

Enhanced security per 802.11i with WEP-40/TKIP/CCMP cipher suite implemented in hardware

The Host needs to feed Data packets (DMA or slave), and to implement selected management operations (JOIN/ASSOCIATION/AUTHENTICATION, 802.1x, 802.11i, QoS management/802.11e). Control packets are built and generated by hardware inclusive (BAckReq and Back) packets.

Due to its hardware implementation data path supports higher speeds then 802.11 rates. It is scalable. It can be customized for higher speed and different wireless protocols like 802.15.3 , 802.16

Available: click Getting an Encrypted Model

802.11e MAC in XILINX 1000 FPGA series 12K FF’s and 20K gates with 48% utilization. It includes packet memory and Buffer Management
RTL code + Test-Bench Code + Documentation Manual
VHDL Evaluation encrypted version of the (MAC + Test-Bench).
Test-Bench in SystemC and C++ also available.
Detailed Documentation, 200 pages Manual, Protocol Procedures.

Major differentiations:

Maximum theoretical throughput (IP frames/second). Maximum wireless medium utilization.
AP or STA or HC or QSTA
Standard DCF and PCF
HC on HCCA. Coexisting with (DCF/PCF/EDCA), packet burst (CFB) and BACKReq, BACK. It has built in precision clock synchronization as specified by 802.11e. It has service interval requirements as specified in 802.11e. It has internal hardware Polling and bandwidth Manager for HC or AP.
Full Direct Link support per packet commanded by the CPU.
Enhanced security per 802.11i with WEP-40/TKIP/CCMP cipher suite implemented in hardware.
Hardware implementation with an internal compact Multi Queue System will eliminate latency time encountered in the software implementation and improve the system performance, medium access, overall throughput in packets per seconds. It implements HC or QSTA requirements with 4 Access Services in HCCA and EDCA mode. In HC mode the number of AC’s can be increased.
Fragmentation/Defragmentation, packet/fragment duplication is implemented internally in hardware. It has no latency during fragmentation/retransmissions or WEP/WEP2/AES.
802.11a/b/g PHY access. Multiple concurrent PHY’s.
Power Save modes for STA in IBSS.
Power Save mode for STA in BSS is enhanced do to the hardware implementation of the Multi Queue System.
All dot11registers are available and configurable.

The Sc1021 MAC supports STA (BSS/IBSS/QBSS/QIBSS) or AP modes. It supports at the transmit/receive all 802.11/802.11e packet formats. It also supports all Power Save modes. The Transmit MAC has multiple queues for QoS, management packets, BCST/MCST data, power save packets. The MAC will fragment unicast packets and perform RTS{CTS}/selfCTS according with per packet LLC requests.

Unique in the industry it has a compact QoS dynamic queuing system for receive and transmit based on linked scattered buffers. The packet memory size is configurable. The queue system is transparent to the user. It supports broadcast, management, QoS packets and bandwidth management, data and packets designated to stations in power save. It has the capability of retransmission of packet/fragment, eliminating duplicate fragments/packets. Due to the queuing system there are no latency times due to the CPU or system latency. The user can dynamically configure the mode of operation.

The Sc1021 MAC supports DCF, PCF, HCCA, EDCA medium access with precise slot timing, back-off procedures and durationID calculation, clock synchronization.

The The Sc1021 has WEP-40/TKIP/CCMP hardware ciphers with on the fly encryption per each packet or fragment. It has slave capabilities to configure and access all MAC resources. The Host has also capabilities to access all 802.11a/ b/g PHY resources.

The Sc1021 MAC will off load the Host/CPU tasks. It will let the Host/CPU deal with higher LLC/MGM protocols, QoS management, gateway to/from Ethernet TCP/IP stack, IP tunneling. The hardware implementation has the advantage that will insure the highest payload throughput and the maximum utilization of the wireless medium. It will be able to support time critical applications with minimum latency and jitter. It supports future evolution of the protocol. This is handled by configuration software.

Sc1021 is also suitable for special application in high speed wireless data communication like first/last mile application, including QoS and bandwidth reservation. An special polling module implemented in hardware for the MAC configured as an AP/HC will maximize the bandwidth utilization. The 802.11e traffic manager will allocate/reserve bandwidth as required and managed by a QAP. The speed is dependable only by the PHY. The Sc1021 MAC can be integrated to an Ethernet router/switch.

Due to its modularity, for application requiring low speed data transfer the MAC can be customized based on pin count, area, cost.

The CPU will dynamic/static configure the MAC with all parameters according with the PHY type and the operation mode.

A comprehensive Test-bench package will fully test the Sc1021. It will provide the majority of procedures for the software driver.

• Full standard implementation

• AHB/APB system I/F and standard 802.11a/b/g PHY I/F

• Support for all Distribution Systems

• STA/QSTA in BSS/EBSS or AP/QAP or QSTA/STA in IBSS/QIBSS

• QSTA in (EDCA or Controlled mode)

• Direct Link support

• Hardware implementation with flexible degree of Host/CPU control.
• Option of Master DMA and Slave mode or Slave only

• Hardware Fragmentation/Defragmentation(concurrent fragments from multiple sources)
• Precise Time Stamping, Hardware precise network clock synchronization.

• Power Save for STA in BSS or IBSS

• Precise Distributed/Enhanced and Point Coordination Function in hardware (DCF/EDCF and/or PCF/QCF).
• Multi Rate support per packet
• Control Packets generated by hardware for precise coordination
• Enhanced security per 802.11i with WEP-40/TKIP/CCMP cipher suite implemented in hardware

• All 802.11/ 802.11e Data, Control and Management packets supported
• Statistics

One of many application example. The example shows different kind of connections to a CPU/Host. Host or Risc CPU gets IP Ethernet packets convert or encapsulate them on 802.11 LLC packets. The MAC will take LLC 802.11 packets and convert them to 802.11 or 802.11e packet format and transmit them over wireless medium according with 802.11 protocol.