Expertise offered by hmw-consulting

The following sections describe our main areas of expertise:

Networking (Layer 1 to 4)

  • Ethernet (802.2 LLC, 803.3)
  • Wireless LAN (802.11a/b/g, 802.11f, 802.1x, WPA)
  • VPN technologies (IPsec, L2TP, PPTP, cipe, OpenVPN)
  • IPv6
  • SCTP
  • Packet Filtering / NA(P)T
  • NAT Application Layer Gateways (ALG)
  • IBM SNA Protocol Stack

(Mobile) Communications

  • ISDN protocols (Q.921, Q.922, Q.931, V.120, X.75)
  • GSM Um Interface (all layers, incl. LAPDm, RLC/MAC, RR/MM/CC, SM/GMM)
  • GSM A-bis (RSL and OML) and A (BSSMAP, BSSAP) interface
  • GPRS Gb interface: LLC, SNDCP, BSSGP, NS protocols
  • GPRS/UMTS Gn interface: GTP Version 0, 1, 2; GTP-C, GTP-U
  • Classic SS7 protocols: MTP2, MTP3, ISUP, SCCP protocols
  • GSM/UMTS core network protocols: TCAP, MAP, CAP protocols
  • SIGTRAN protocols: M2PA, M2UA, M3UA, SUA protocols
  • UMTS Iu protocol stack: NBAP, RRC, RANAP protocols
  • UMTS Iuh protocol stack (HNBAP, RUA, RANAP)
  • SMPP 3.4 Protocol
  • TETRA V+D protocol stack, specifically PHY, MAC and LME
  • SIM / USIM / UICC related ETSI and 3GPP protocols
  • Security related aspects of abovementioned protocols

Networking (Layer 5+)

  • Networking File Systems (NFS, SMB)
  • Application layer security (SSL, TLS)
  • Socks Proxies
  • Transparent Proxies
  • VoIP Protocols (SIP/SDP, H.323)
  • Dynamic Routing Protocols (RIP, OSPF, BGP)


While hmw-consulting doesn't provide expertise in developing RDBMS, we can offer database modelling and software development interfacing with the following database systems: - Oracle 8+ - MySQL - PostrgreSQL - LDAP directory services

Linux Kernel Development

  • Device Drivers (Networking, Power Management Unit, Graphics, sensors, USB device)
  • Networking Protocols, Packet Filter
  • Architecture Porting
  • Integrating code with upstram / mainline Linux

Embedded Devices

hmw-consulting has experience in both hardware architecture design as well as software / driver development based on the following products

  • 80C51 based microcontrollers (80c535, EzUSB, P8RF5016)
  • 80C166 microcontrollers
  • Embedded x86 Hardware (Geode, C3/C7, AMD APU, Intel Atom)
  • Texas Instrumenst Calypso/Iota/Rita GSM chipset
  • ARM7/ARM9/ARM11 embedded cores
  • Cortex-M0 and Cortex M3 based microcontrollers
  • STMicro STM32F1xx, STM32F05x, STM32F2xx microcontrollers
  • Intel pxa255/pxa270 SoC
  • TI OMAP2xxx and OMAP3xxx SoC
  • TI DaVinci SoC
  • TI Sitara AM335x SoC
  • Samsung S3C2410, S3C2440, S3C2442, S3C2443, S3C64xx, S5PC1xx, S5PV210 SoC
  • Smedia Glamo embedded graphics accelerators
  • Philips/NXP power management units (pcf50606, pcf50633)
  • Smartphone hardware development
  • u-boot bootloader driver implementation and porting to new boards

Programming Languages

  • C
  • C++
  • Pascal
  • Perl
  • Python
  • Assembly (x86, x86_64, PowerPC, 80c51, ARM, Thumb)
  • Erlang/OTP
  • TTCN-3 (specifically using Eclipse TITAN)

PC Hardware

While not providing any consulting for hardware development, hmw-consulting has a strong background in OS and Firmware development. Thus, low-layer knowledge about the following PC hardware technologies and their common register sets and software interfaces

  • USB / USB 2.0 / USB 3.0
  • IEE1394 / FireWire
  • PCI / PCI-X / PCI Express
  • HyperTransport
  • PowerPC (G3, G4, G5)
  • AMD64 / x86_64 / Opteron
  • ARM7 / ARM9 / Xscale / ARM11 / Cortex-A
  • Intel IXP24xx/28xx Network Processors


  • Smart Card (Chip card) reader driver development (PC/SC, CT-API)
  • DIN EN ISO/IEC 7816-4 based cryptographic smartcards
  • DIN EN ISO/IEC 7816 secure messaging
  • German signature law (SigG) standards
  • HBCI standards / protocols
  • ICAO MRTD (ePassport) related development
  • SIM / USIM / UICC related ETSI and 3GPP protocols
  • Java Card standards (including Global Platform)


  • ISO 14443-3 A+B / ISO 14443-4 protocol stack and PCD drivers
  • ISO 15693 protocol stack and VCD drivers
  • ISO 18000 protocol stack and drivers
  • MiFARE PCD-side software stack development
  • ICAO MRTD (ePassport) related development
  • 13.56MHz RFID reader hardware development

Free Software Licensing

  • (L)GPL compliance in mixed free/proprietary products
  • (L)GPL auditing of existing products
  • Consulting on best current practices in (L)GPL related software development
  • Verification of GPL violations by dissection of object code