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Featured Talent – Communications and Technology Professional – Digium Certified Asterisk Professional (dCAP)

D o u g l a s G a r s t a n g

Digium Certified Asterisk Professional (dCAP)

Cell: (805) 340-5627. Email: [email protected]

Last Updated: Apr 3, 2007

Goal Statement

To architect, design, build, implement and deploy carrier class Voice-Over-IP solutions and applications using the Asterisk PBX platform, and other open source technologies in Montana. To push all expectations, both personal and industry wide, of the solutions that Asterisk and associated technologies can provide. To grow and learn new personal and professional skills in the process. To establish myself as a valuable member of a team in, a company that I feel a strong sense of commitment to.

Skill Summary

Voice-Over-IP(VoIP)/IPT:

Protocols: SIP, RTP, SDP, ENUM, DNS SRV, IAX, G711, G729 etc.. Software: Asterisk, OpenSER(SIP Express Router). RFC’s: 3261, 1889, 2327. Hardware: Polycom SoundPoint IP 301/501/601 phones, Audicodes Mediant 2000 Gateway. Advanced asterisk features including complex configuration via native configuration files, realtime, AGI, Fast AGI with multithreaded python/perl, MySQL. Implementation of advanced architectural features including busy lamp field, ACD queues, meetme conferencing, blacklists, whitelists, PIC code insertion, rate centers, findme/followme, user profiles. MySQL database design for advanced call routing. Configuration of SIP express router at native configuration file level.

Networking:

IP, TCP, UDP, DHCP, DNS, FTP etc

Storage Technology:

Storage area networks(SAN’s), RAID levels, fibre-channel topology (loop, fabric), fibre-channel infrastructure devices (brocade, qlogic, emulex), port and WWPN zoning, lun masking, storage virtualization, high availability(HA), load balancing, dynamic multi-pathing(DMP) with VxVM, AIX MPIO, IBM RDAC, StoreAge VSD and VMware ESX, SAN data concepts including snapshots (copy on write), online migration, mirroring, fibre-channel HBA’s, HBA drivers (Emulex, Qlogic, JNI), StoreAge product suite, Apcon patch panels

Storage Hardware:

EMC Clariion CX-200, Hitachi 9200, Hitachi 9900, IBM FastT, IBM DF4000R, LSI/Engenio 2882, Eurologic, MTI, Dell, other assorted RAID arrays and JBOD’s.

Operating Systems:

Linux Gentoo, Red Hat, Fedora Core 3/4, Mandrake, SLS, Slackware and Debian, Sun Solaris sparc/x86 2.7, 2.8, 2.9, 2.10, VMWare ESX Server, Windows 2000 Advanced Server and Windows XP, FreeBSD, MS-DOS

Software and Applications:

EMC Navisphere, Veritas Volume Manager, Veritas File System, Veritas Servpoint SAN, Postgres database, Sun custom Jumpstart, Linux Kickstart, Linux Debian FAI, Finisar XGig and ITech fibre-channel protocol analyzer software, Unix command line environments, The Software Testing Automation Framework(STAF), Office productivity tools

Development:

Perl (and various modules), Perl DBI, Python (and various modules), shell scripting (sh, ksh, bash), Tcl/Tk, expect, CGI, HTML, SQL, javascript, Java, C, network client-server programming, regex text parsing, test automation, remote device control.

Hardware:

Sun hardware, Ultra 5/10/60/80, Enterprise E3500/E220R/E420R/E250R, SunFire E280R, Netra T, Intel X86 hardware including Compaq DL, Dell 1850, 2650.

Miscellenaneous:

Voice Over IP (VoIP), TCP/IP, X.400, X.25, EDI

Certification and Training

Digium:

09/2006: Asterisk Bootcamp

09/2006: Certification: Digium Certified Asterisk Professional (dCAP)

Storage Networking Industry Association:

03/2005: Training: SNIA Storage Fundamentals Workshop

03/2005: Certification: SNIA Certified Professional (SCP)

Sun Microsystems:

03/2002: Certification: Sun Certified System Administrator for Solaris 2.8

04/2002: Certification: Sun Certified Network Administrator for Solaris 2.8

Veritas:

12/2001: Training: Veritas Volume Manager for Solaris 3.1.1

12/2001: Training: Veritas File System for Solaris 3.4

Education

Bachelor of Business, Computing and Information Management
University of Western Sydney, 1991 – 1994

Career Summary

VoIP Engineer/Asterisk Programmer – Jan 2007 to Present

TalkPlus, San Mateo, CA

Achievements:

• Built a multi-cluster, multi-node state machine in Java to monitor events and send commands to Asterisk systems.

• Built a complex custom voicemail application (over 3000 lines of code) in the Asterisk dial plan.

VoIP Applications Convergence Engineer – Sep 2005 to Jan 2007

OneEighty Communications, Billings, MT

Purpose:

My responsibility was to personally implement, with minimal direction, a hosted IP telephony product for a Competitive Local Exchange Carrier(CLEC) (ie a telephone company) from conception to product release, and beyond. Critical requirements that I personally implemented for this system included carrier class system redundancy, scalability, and a myriad of business related, telephony feature sets, for customers. Redundancy was a fundamental requirement of the product. As a result, I architected the ability of the system as a whole to undergo single or multiple component failures virtually anywhere, with little or no impact on customers. Scalability was also a requirement. I designed the system such that new nodes could be added to increase concurrent call processing capacity. This new product was designed to work in conjunction with One Eighty’s Lucent 5ESS switch, eventually replacing it as One Eighty moved to a soft switched environment.

Achievements:

• During initial evaluation, performed extensive research into the use of various soft-switching software as potential platforms for the new hosted IP telephony product, including those of Sylantro, Communigate, PingTel, Digium’s Asterisk, and IPTel’s SER (SIP Express Router). Engaged with product management in detailed discussion regarding the advantages, disadvantages and ability of each platform to meet requirements.

• Designed, built and programmed the SIP proxy components of the IP telephony product, using the OpenSER SIP Express Router.

• Designed, built and programmed the PBX components of the IP telephony product, using the Asterisk open source PBX. The PBX components added the extensive feature sets required by One Eighty’s business (not residential) customers.

• Configured the PSTN gateways, Audiocodes Mediant Gateways.

• Applied high availability and redundancy protocols to the relationships between all functional components in the architecture. This insured single or multiple components in the system could fail with little or no impact on the ability of customers place calls.

• Ordered, racked and installed the IP telephony product application servers. Installed Gentoo Linux on all servers, and all necessary utilities and applications. Performed constant tweaking and modifications to operating systems and software to suit requirements.

• Designed, built, and programmed the auxiliary hosted IP telephony services, including DHCP, DNS, FTP and SNTP.

• Provisioned, with little assistance, customer premises hand sets, the Polycom Sound Point 501, Sound Point 601, and Sound Station 4000 telephones. This included extensive configuration of the very large XML configuration files.

• Directed a team of consultants in the design of a custom MySQL database schema to be used as the core for all advanced call routing feature sets.

• Developed an Asterisk AGI python dial plan application that was the ‘brains’ for all call routing. It queried a MySQL database in real time and controlled all call flow. Features controlled by the AGI application included calling blacklists and white-lists for incoming and outgoing calls, feature access, findme/followme, PIC codes and rate centers, various levels of caller ID, casual dialing, star code enabled features, paging and intercom modes, and more.

• Wrote custom utility and ‘glue’ scripts in perl, python and other scripting languages as necessary to aid in the construction of the hosted IP telephony product.

• Integrated the Asterisk Voicemail system and Asterisk ACD queue functions with the customer premises Polycom handsets for ease of use. This allowed one-touch voicemail retrieval, and one-touch ACD agent logins. Configured and modified the Asterisk Voicemail system as required.

• Configured Sipura Analog Telephone Adapters (ATA’s) to allow PSTN-to-IP and IP-to-PSTN call routing. Configured the Asterisk PBX dial plan to accommodate the ATA’s.

• Worked with members of the operations team, and regularly discussed matters of security for the IP telephony product.

• Wrote extensive documentation for the ongoing maintenance of the system.

• Performed regular trouble-shooting, and diagnosis of problems as they arose with the new product. Regularly used tools such as ethereal, ngrep, and syslog in problem diagnosis. Performed extensive debugging SIP traffic between systems components.

Unix (Solaris/Linux) System Administrator / Integration Engineer – Nov 2000 to Sep 2005

Troika Networks, Westlake Village, CA

Achievements:

• Performed SAN interoperability and integration testing in a complex, non-heterogeneous, multi-vendor, SAN environment.

• Integrated various vendor LVM/HA/DMP software products as needed under various operating systems with the Troika Accelera SAN appliance.

• Developed test automation tools in Perl and Python to test LVM/HA/DMP products.

• Developed and documented an object-oriented test automation API in Perl and Python to test a complex SAN environment, and control various SAN devices such as switches, power sentries, user interfaces, proprietary appliances, storage arrays and host operating systems. Operating systems included Linux, Solaris, VMWare ESX, Windows, HP/UX, AIX and Tru64.

• Managed various storage arrays to allocate storage, and other SAN infrastructure devices such as switches as needed.

• Automated and standardized the installation of Sun test systems with Solaris Custom Jumpstart, and Linux systems with Red Hat Kickstart.

• Performed QA testing and troubleshooting of in-house built (Troika Zentai) fibre-channel HBA’s, and SAN appliances (Troika Accelera) running Linux.

• Made operating system modifications as needed to achieve correct or optimum configurations in a SAN environment, such as modifying and recompiling Linux kernels.

• Performed Sun Solaris administration and provided Sun support to multiple departments.

• Provided support in a quality assurance and development environments for various Sun hardware platforms.

• Built various utilities with Perl, Java and raw HTML to assist in the allocation of Sun test systems.

• Worked with software engineers in a highly iterative manner to debug and diagnose software and firmware problems.

• Worked with external vendors to debug problems.

• Tracked issues and maintained accountability until problem resolution.

Voice-Over-IP Consultant(Contract) – Jul 2000 to Aug 2000
Interline Networks, Sydney, Australia

Achievements:

• Assisted the new company management with the re-establishment of the business by providing advice in key areas.

• Constructed operations tools to assist with host and network monitoring.

• Performed overdue Unix administration and maintenance on operations servers.

• Provided training to new staff in Sydney and Melbourne.

• Drove the establishment of new infrastructure projects and new customers.

• Improved VoIP quality of service by monitoring and raising telephone call completion rates.

Perl Web Developer(Contract) – Dec 1999 to Jul 2000
News Corporation, Sydney, Australia

Achievements:

• Creation of automatic Oracle data loading systems.

• Developed a series of tools to take television programming data from approximately 35 different television channels for upload into to Oracle.

• Developed tools to convert online media content to XML for distribution via SMS to cell phones.

• Wrote technical development specifications for various projects.

• Constructed list manager software.

Voice-Over-IP Operations Tech Leader – Aug 1998 to Nov 1999
OzEmail Interline, Sydney, Australia

Achievements:

• Developed monitoring tools in Perl, ksh, sed, expect and SQL.

• Provision of real-time Voice-Over-IP capacity planning raw data and graphs.

• Collection of real-time Voice-Over-IP call quality metrics raw data and graphs.

• Operating System monitoring of the Sun hardware controllers situated in Sydney, Los Angeles and San Jose. Data sent back to a central server in Sydney via a TCP/IP client/server mechanism.

• Voice-Over-IP node/gateway operating system and application monitoring via a custom written TCP/IP server application interfaced to via a web page.

• Provided initial training and ongoing technical assistance for new staff members.

• Installed, configured and maintained the company mail relay for the domain interline.aust.com.

• Performed Y2K upgrades to Voice-Over-IP equipment in San Jose, Los Angeles, and New York.

• Collection of ASR (average success rate) Voice-Over-IP call completion records to every telephone area code to every country in the world on an hour-by-hour basis. Development of web pages and email to display results, and highlight areas of concern.

• Creation of several monitoring machines running Linux to be used in typical Network Operations Centre style. Involved installation of Red Hat Linux, Apache web server, X11R6, secure shell etc.

• Creation of quick reference reports showing telephony routing for all areas every three hours.

Unix System Administrator / Business Partner – Mar 1998 to Jun 1998

Wolf Computer Solutions, Sydney, Australia

Achievements:

• Monitored and support the day to day running of the various Unix systems, servers and network.

• Performed routine nightly backups and regular offsite backups including utility software to run the back procedures.

• Web page & web site configuration, design and creation ranging from technical configuration of the web server to creative design of customer web sites.

• Creation and ongoing maintenance of system and network utilities, written in Perl, Unix shell scripts and HTML.

• Maintained the domain name system, including configuration and the application to relevant domain authorities.

• Maintained the internal networks security.

• Implemented fault tolerant and warning systems to be triggered under certain conditions, such as loss of network connectivity.

• Provided technical support to both dial up and web hosting customers including technical telephone support for new and existing users and installation of the necessary software on customer computers.

• Installation and configuration of servers including DNS (Domain name server), Proxy, ftp, www, news, mail and games servers.

• Performed network management and design.

• Tested and resolved problems with the systems and network configurations as they arose.

• Participated as an active participant in both the day-to-day and long term strategic planning of the business

Technical Customer Support Representative – Nov 1995 to Mar 1998

Telstra Multimedia, North Sydney, Australia

Technical Customer Support Representative – Aug 1995 to Nov 1995
Simple Retail, Sydney, Australia

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