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Title Date Added Company

Expected Data Rate: An Accurate High-Throughput Path Metric for Multi-Hop Wireless Routing 0000-00-00 University of Utah

This paper presents a new metric, Expected Data Rate (EDR), for accurately finding high-throughput paths in multihop ad hoc wireless networks. The metric is based upon a new model for transmission interference which is a critical factor in determining path throughput. This paper constructs a realistic and practical transmission interference model by determining transmission contention degree of each link as a function of the wireless link loss; quantifying the impact of the wireless link loss on medium access bakeoffs; and considering possible concurrent transmissions when two links do not interfere with each other. The transmission interference model also takes the non-optimality of IEEE 802.11 medium access scheduling into account.

Tags: Mobile - Wireless Communications, Wi-Fi (802.11)

Facing a Real-Life Issue: Upgrading Outdated Communications Systems 2006-11-01 01:00:28 Panasonic

Using an obsolete communications system can be dangerous, as learned by a rapidly growing city just north of Nashville, Tennessee. The city's communication system, which covered all municipal functions, such as police, fire, water, and more, needed to be replaced due to the difficulty of obtaining parts and appropriate service for their aging system - and with the growing population, the importance of upgrading was highlighted. The city needed a unified phone system that would seamlessly connect multiple sites, and consolidate multiple systems - but keeping cost and ease-of-implementation in mind.

Fast forward to post-upgrade: common technology, such as centralized voice mail, direct extensions, and wireless/desktop phones, is now experienced - but cost effectively. In addition to these benefits, vital security was increased across the city with the implementation of door-opener cards for employees and key city leaders. This white paper takes a look at the issues originally faced, which are still faced by many businesses today, and details the cost-effective and secure solutions selected, along with an overview of its easy implementation.

Why Wait? Get Unified Commmunications for Exchange Now 2006-10-31 15:35:07 Adomo

Over the past several months, much has been said of Microsoft's announcement of unified communications functionality in Exchange 2007. A lot of it is good: a single desktop client (Outlook), integration with Live Communications Server, and message access via a variety of devices, including mobile phones and PDAs. And much causes concern: Exchange 2007 will only work on 64-bit servers and cannot co-exist with some older Exchange servers. Moving from your TDM phone system to VoIP on Exchange will have to be a flash cut; no phased migration for your multiple offices or phone systems. And if Exchange is unavailable, then voice messages cannot be delivered or received.

Learn how to extend unified communications functionality to Exchange 2000 and 2003. Adomo provides unified communications and intelligent mobility on a hardened appliance platform and connects to traditional TDM and new IP PBX systems, out of the box.

Layer 3 Malformed Packet Testing in MCI's Public IP Network 2005-10-20 09:50:11

Malformed packets associated with routing protocols can cause undesirable consequences if not detected and contained properly as close to the originator as possible. This issue magnifies in scope and complexity in a large-scale network, such as a public IP network. A malformed routing packet has the potential to impact thousands of customers as well as all the major Internet service providers (ISP) in a matter of seconds. This paper discusses internally developed techniques that enable engineers to study the response in a lab environment and insure that these packets cause no disruption to network operations. These measures have been implemented for almost three years and during this time no major outage has occurred due to malformed Border Gateway Protocol (BGP) or Intermediate-System to Intermediate-System (ISIS) packets in the MCI public IP network.

Cisco Network Solutions for the Telco DCN: Transmission Equipment in X.25 Environments 2006-12-14 01:00:24 Cisco Systems

This paper is directed to Competitive Local Exchange Carriers (CLECs), Incumbent Local Exchange Carriers (ILECs), and Post, Telephone, and Telegraphs (PTTs), telephone companies collectively referred to as telcos. The paper describes Cisco network solutions for transporting data between various transmission network elements and the Operations Support System (OSS) in a telco's Data Communications Network (DCN). The DCN transports network management traffic between network elements and their respective OSS, making them a vital link between the service network and the Network Operations Center (NOC). The solutions presented in this paper will help telcos migrate transmission equipment that use the X.25 protocol to a router-based TCP/IP network.

All-Digital TX Frequency Synthesizer and Discrete-Time Receiver for Bluetooth Radio in 130-nm CMOS 2005-10-13 03:00:02

The paper presents a single-chip fully compliant Bluetooth radio fabricated in a digital 130-nm CMOS process. The transceiver is architectured from the ground up to be compatible with digital deep-submicron CMOS processes and be readily integrated with a digital base-band and application processor. The conventional RF frequency synthesizer architecture, based on the voltage-controlled oscillator and the phase/frequency detector and charge-pump combination, has been replaced with a digitally controlled oscillator and a time-to-digital converter, respectively. Application of the presented ideas has resulted in significant area and power savings while producing structures that are amenable to migration to more advanced deep-submicron processes, as they become available.

Capacity Gains of Single Antenna Interference Cancellation in GSM 2005-11-29 01:00:03

Single Antenna Interference Cancellation (SAIC) is a very interesting and promising technology currently being standardized in 3GPP as part of GERAN Release 6. This interference reduction technique takes advantage of the latest developments in signal processing and receiver algorithms in a cost-efficient way. In most advantageous interference conditions, SAIC can improve the signal-to-noise ratio over 10 dB. In this paper, the effect SAIC on the capacity of a typical GSM network are investigated. Also, an overview of SAIC algorithms is presented and a new interface for mapping the link and network simulator is described.

Next-Generation Optical Transmission Fibers 2005-10-20 09:30:06

The first part of this paper gives a brief introduction of modern optical transmission fiber technology. The second part of this paper illustrates detailed numerical analysis, lab tests, and field trials of MCI's next-generation fiber development process from 2000 to 2005. The new Medium Dispersion Fiber (MDF) has dispersion of around 7~8 ps/nm/km at 1550nm, and a relatively low dispersion slope in the S-C-L band, which will satisfy MCI next-generation transmission fiber technical specifications and requirements at 20 Pb/s*km for "short fat" (20 Tb/s x 1000 km) and "long thin" (6.67 Tb/s x 3000 km) future DWDM, Metro, Regional, and ULH network application and deployment. The development and deployment of this extremely high-optical performance fiber will help the telecommunications industry to introduce new applications and keep MCI at the forefront of optical transmission technology around the world.

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Title	Date Added	Company
Expected Data Rate: An Accurate High-Throughput Path Metric for Multi-Hop Wireless Routing	0000-00-00	University of Utah
This paper presents a new metric, Expected Data Rate (EDR), for accurately finding high-throughput paths in multihop ad hoc wireless networks. The metric is based upon a new model for transmission interference which is a critical factor in determining path throughput. This paper constructs a realistic and practical transmission interference model by determining transmission contention degree of each link as a function of the wireless link loss; quantifying the impact of the wireless link loss on medium access bakeoffs; and considering possible concurrent transmissions when two links do not interfere with each other. The transmission interference model also takes the non-optimality of IEEE 802.11 medium access scheduling into account. Tags: Mobile - Wireless Communications, Wi-Fi (802.11)
Facing a Real-Life Issue: Upgrading Outdated Communications Systems	2006-11-01 01:00:28	Panasonic
Using an obsolete communications system can be dangerous, as learned by a rapidly growing city just north of Nashville, Tennessee. The city's communication system, which covered all municipal functions, such as police, fire, water, and more, needed to be replaced due to the difficulty of obtaining parts and appropriate service for their aging system - and with the growing population, the importance of upgrading was highlighted. The city needed a unified phone system that would seamlessly connect multiple sites, and consolidate multiple systems - but keeping cost and ease-of-implementation in mind. Fast forward to post-upgrade: common technology, such as centralized voice mail, direct extensions, and wireless/desktop phones, is now experienced - but cost effectively. In addition to these benefits, vital security was increased across the city with the implementation of door-opener cards for employees and key city leaders. This white paper takes a look at the issues originally faced, which are still faced by many businesses today, and details the cost-effective and secure solutions selected, along with an overview of its easy implementation.
Why Wait? Get Unified Commmunications for Exchange Now	2006-10-31 15:35:07	Adomo
Over the past several months, much has been said of Microsoft's announcement of unified communications functionality in Exchange 2007. A lot of it is good: a single desktop client (Outlook), integration with Live Communications Server, and message access via a variety of devices, including mobile phones and PDAs. And much causes concern: Exchange 2007 will only work on 64-bit servers and cannot co-exist with some older Exchange servers. Moving from your TDM phone system to VoIP on Exchange will have to be a flash cut; no phased migration for your multiple offices or phone systems. And if Exchange is unavailable, then voice messages cannot be delivered or received. Learn how to extend unified communications functionality to Exchange 2000 and 2003. Adomo provides unified communications and intelligent mobility on a hardened appliance platform and connects to traditional TDM and new IP PBX systems, out of the box.
Layer 3 Malformed Packet Testing in MCI's Public IP Network	2005-10-20 09:50:11
Malformed packets associated with routing protocols can cause undesirable consequences if not detected and contained properly as close to the originator as possible. This issue magnifies in scope and complexity in a large-scale network, such as a public IP network. A malformed routing packet has the potential to impact thousands of customers as well as all the major Internet service providers (ISP) in a matter of seconds. This paper discusses internally developed techniques that enable engineers to study the response in a lab environment and insure that these packets cause no disruption to network operations. These measures have been implemented for almost three years and during this time no major outage has occurred due to malformed Border Gateway Protocol (BGP) or Intermediate-System to Intermediate-System (ISIS) packets in the MCI public IP network.
Cisco Network Solutions for the Telco DCN: Transmission Equipment in X.25 Environments	2006-12-14 01:00:24	Cisco Systems
This paper is directed to Competitive Local Exchange Carriers (CLECs), Incumbent Local Exchange Carriers (ILECs), and Post, Telephone, and Telegraphs (PTTs), telephone companies collectively referred to as telcos. The paper describes Cisco network solutions for transporting data between various transmission network elements and the Operations Support System (OSS) in a telco's Data Communications Network (DCN). The DCN transports network management traffic between network elements and their respective OSS, making them a vital link between the service network and the Network Operations Center (NOC). The solutions presented in this paper will help telcos migrate transmission equipment that use the X.25 protocol to a router-based TCP/IP network.
All-Digital TX Frequency Synthesizer and Discrete-Time Receiver for Bluetooth Radio in 130-nm CMOS	2005-10-13 03:00:02
The paper presents a single-chip fully compliant Bluetooth radio fabricated in a digital 130-nm CMOS process. The transceiver is architectured from the ground up to be compatible with digital deep-submicron CMOS processes and be readily integrated with a digital base-band and application processor. The conventional RF frequency synthesizer architecture, based on the voltage-controlled oscillator and the phase/frequency detector and charge-pump combination, has been replaced with a digitally controlled oscillator and a time-to-digital converter, respectively. Application of the presented ideas has resulted in significant area and power savings while producing structures that are amenable to migration to more advanced deep-submicron processes, as they become available.
Capacity Gains of Single Antenna Interference Cancellation in GSM	2005-11-29 01:00:03
Single Antenna Interference Cancellation (SAIC) is a very interesting and promising technology currently being standardized in 3GPP as part of GERAN Release 6. This interference reduction technique takes advantage of the latest developments in signal processing and receiver algorithms in a cost-efficient way. In most advantageous interference conditions, SAIC can improve the signal-to-noise ratio over 10 dB. In this paper, the effect SAIC on the capacity of a typical GSM network are investigated. Also, an overview of SAIC algorithms is presented and a new interface for mapping the link and network simulator is described.
Next-Generation Optical Transmission Fibers	2005-10-20 09:30:06
The first part of this paper gives a brief introduction of modern optical transmission fiber technology. The second part of this paper illustrates detailed numerical analysis, lab tests, and field trials of MCI's next-generation fiber development process from 2000 to 2005. The new Medium Dispersion Fiber (MDF) has dispersion of around 7~8 ps/nm/km at 1550nm, and a relatively low dispersion slope in the S-C-L band, which will satisfy MCI next-generation transmission fiber technical specifications and requirements at 20 Pb/s*km for "short fat" (20 Tb/s x 1000 km) and "long thin" (6.67 Tb/s x 3000 km) future DWDM, Metro, Regional, and ULH network application and deployment. The development and deployment of this extremely high-optical performance fiber will help the telecommunications industry to introduce new applications and keep MCI at the forefront of optical transmission technology around the world.