Category Archives: Transportation

A Transportation Management System Can Help Businesses Grow

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Managing the supply chain for a business is a daunting but necessary task. There are many transportation management systems available today. Transportation management systems are computer based software companies intended to manage transport operations and deals. They assist a company in controlling the day to day processes involved in transportation of their goods. These critical systems have made real time execution and information retrieval more mainstream.

With many various transport companies and services available, it is important to consider what particular services are most vital to the success of one’s business.

There are three options available. First, the traditional version in which they purchase traditional on-premises licenses; Second, the remote version in which it is web hosted; and Third, on premises hosted licensing which blends the first two together.

A blended system has quickly grown in popularity because of the additional flexibility that it provides a business. When a company chooses a blended transportation management system, it receives not only real-time usage and but also freight capacity. Often the software is provided for little to no cost and then a company pays for the freight capacity service.

The various transport management companies will help companies determine the best truck routes and shipping options. They will review the company’s needs and then implement systems based on whatever is most important to the shipping customer. They may focus on cost to transport, better lead-times, or the least amount of stops.

A Transport Management System (TMS) also helps with important follow up responsibilities. The system can do the billing and invoicing for shipment, track shipment details, and monitor warning regarding delays with planned shipments.

Another great tool that makes a blended TMS a good investment is that they can also measure how well a business’ supply chain functions. It has real time vehicle tracking, true transport cost and customer service control.

A company can truly profit from the Key Performance Indicators which involves tracking and reporting statistics. Transportation managers can determine how much a load cost down to the pound to transport. Being aware of the true cost to ship something can help a business better budget for such needs and also measure how well a company is doing comparatively to previous quarters or years. Along with this feature they can also track the percentage of on-time deliveries and pickups. Because this can affect the cost of shipment, it is important to monitor.

When a company makes the decision to use blended transportation management software, they do so to increase the overall effectiveness of the business. A blended TMS also encourages the company to be financially frugal without giving up the ability to customize the software to best fit their needs. Because a company is always striving to be more customer-service orientated, having an excellent way to track shipments, problems, and deliveries is a very valuable quality of the software. Another positive aspect of blended software is being able to know the total cost that a company spends on shipping so that the company can become more fiscally responsible.

Finally, while every business would benefit from a transportation specialist, those who utilize a blended system can enjoy overall cost savings, positive training and support for a traditional Transport Management System.

Wavelength Service in Optical Transport Networks

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Optical WDM (Wavelength Division Multiplexing) networks are networks that deploy optical WDM fiber links where each fiber link carries multiple wavelength channels. An All Optical Network (AON) is an optical WDM network which provides end-to-end optical paths by using all optical nodes that allow optical signal to stay in optical domain without conversion to electrical signal. AONs are usually optical circuit-switched networks where circuits are switched by intermediate nodes in the granularity of a wavelength channel. Hence a circuit-switched AON is also called a wavelength routing network where optical circuits are equivalent to wavelength channels.

A wavelength routing network consists of optical cross-connects (OXC) and optical add/drop multiplexers (OADM) interconnected by WDM fibers. Transmission of data over this optical network is done using optical circuit-switching connections, known as lightpaths. An OXC is an N x N optical switch with N input fibers and N output fibers with each fiber carries W wavelengths. The OXC can optically switch all of the incoming wavelengths of its input fibers to the outgoing wavelengths of its output fibers. An OADM can terminate the signals on a number of wavelengths and inserts new signals into these wavelengths. The remaining wavelengths pass through the OADM transparently.

In order for a user (router A) to transmit data to a destination user (router B), a circuit-switching connection is established by using a wavelength on each hop along the connection path. This unidirectional optical path is called a lightpath and the node between each hop is either an OXC or an OADM. A separate lightpath has to be established using different fibers to set up transmission in the opposite direction. To satisfy the wavelength continuity constraint, the same wavelength is used on every hop along the lightpath. If a lightpath is blocked because the required wavelength is unavailable, a converter in an OXC can transform the optical signal transmitted from one wavelength to another wavelength.

Since the bandwidth of a wavelength is often much larger than that requires by a single client, traffic glooming is used to allow the bandwidth of a lightpath to be shared by many clients. The bandwidth of a lightpath is divided into subrate units; clients can request one or more subrate units to carry traffic streams at lower rates. For example, information is transmitted over an optical network using SONET (Synchronous Optical Network) framing with a transmission rate of OC-48 (2.488 Gbps). A lightpath is established from OXC1 to OXC3 through OXC2 using wavelength w, the subrate unit available on this lightpath is OC-3 (155 Mbps). A user on OXC1 can request any integer number of OC-3 subrate units up to a total of 16 to transmit data to another user on OXC3. A network operator can use traffic-groomed lightpaths to provide subrate transport services to the users by adding a virtual network to the optical network.

Information on a lightpath is typically transmitted using SONET framing. In the future, the information transmitted over optical network will use the new ITU-T G.709 standard, known as digital wrapper. In ITU-T, an optical network is referred to as the optical transport network (OTN). The following are some of the features of G.709 standard:

1) The standard permits transmission of different types of traffic: IP packets and gigabit Ethernet frames using Generic Framing Procedure (GFP), ATM cells and SONET/SDH synchronous data.
2) It supports three bit rate granularities: 2.488 Gbps, 9.95 Gbps and 39.81 Gbps.
3) It provides capabilities to monitor a connection on an end-to-end basis over several carriers, as well as over a single carrier.
4) G.709 uses Forward Error Correction (FEC) to detect and correct bit errors caused by physical impairments in the transmission links.

Lightpath can either be static or dynamic. Static lightpaths are established using network management procedures and may remain up for a long time. Virtual Private Networks (VPN) can be set up using static lightpaths. Dynamic lightpaths are established in real time using signaling protocols, such as IETF’s GMPLS (Generalized Multi-Protocol Label Switching) and UNI (User Network Interface) proposed by Optical Internetworking Forum (OIF). GMPLS is an extension of MPLS and was designed to apply MPLS label switching techniques to Time Division Multiplexing (TDM) networks and wavelength routing networks, in addition to packet switching networks. The OIF UNI specifies signaling procedures for clients to automatically create, delete and query a connection over wavelength routing network. The UNI signaling is implemented by extending the label distribution protocols, LDP and RSVP-TE.