Home > Articles > Programming > Java

Java Patterns for MPLS Network Management, Part 1

Ever wonder why programming always seems to take longer than expected? Or why what appeared to be simple tasks often end up being very difficult? Many developers don’t use programming patterns nearly as often as they should. In this article, Stephen Morris shows how MPLS network management can be simplified using two Java patterns.
Like this article? We recommend

Like this article? We recommend

The networking industry often reminds me of the 1980s pre-IBM PC software sector—you can have anything as long as it’s a proprietary solution! Characterized by many competing vendors, the networking industry now labors under the burden of non-standard, multivendor architectures. This is seen in service provider and enterprise networks in the form of an overly rich mix of software and hardware cobbled together to provide a growing range of services. Traditional service revenues are shrinking as demand for bandwidth and the demand for new real-time services is growing.

Cisco Systems is emerging as the dominant vendor, but its products are still de facto standards. The lack of a standard platform is complicating the migration to converged IP-based networks. As in the 1980s software industry, the problem is the need for a convergence technology that provides a standard platform (just as the IBM PC and DOS operating system did back then).

Today, MPLS has moved beyond the hype and is still a good candidate for providing such a platform; MPLS is being deployed worldwide by hundreds of service providers. So, why is MPLS so special compared to its predecessors ATM and Frame Relay (FR)? In a nutshell, ATM and FR have scalability problems and they don’t provide easy integration with IP. MPLS succeeds by leveraging proven IP protocols and separating control and forwarding into distinct components.

Componentizing control and forwarding means that the former can be made arbitrarily complex without compromising the packet forwarding mechanism. The control component can be used to perform complex algorithms on incoming IP traffic, such as queue assignment and path selection while leaving the forwarding component untouched. This separation means that forwarding can be performed in hardware if required. Let’s now take the dime tour of MPLS.

MPLS Nuts and Bolts

MPLS provides the following major elements:

  • A virtual circuit-based model (rather than IP hop-by-hop) are called label switched paths (LSPs). One of the Java patterns I use illustrates virtual circuits.
  • Nodes that understand IP and MPLS are typically called label edge routers (LERs). LERs encapsulate traffic from the outer domain. This traffic can be either layer 2 (Ethernet, ATM, FR, etc.) or layer 3 (IP).
  • Core nodes inside the MPLS domain are called label switching routers (LSRs).
  • Traffic engineering (TE) allows traffic to be explicitly directed through the core.
  • Quality of service (QoS) allows resource reservation for different traffic types—e.g., bandwidth, queues, colors, etc. IP offers just one QoS level: Best Effort.
  • Migration from legacy technologies, such as ATM and FR.
  • Differentiated Services allows specific traffic to enjoy better service—e.g., real-time voice packets versus email packets.
  • Deployment of IP-based services such as layer 2 and layer 3 VPN.

We’ll see most of these in the following discussion. Figure 1 illustrates a corporate HQ with a remote branch office interconnected by a service provider network. The HQ site enterprise architecture supports a range of applications, including voice-over-IP (VoIP), video-over-IP, email, etc. Access to these applications is available over the MPLS-based service provider network.

Figure 1 illustrates two LSPs (LSP 1 and LSP 2). Both LSPs have been configured with explicit route objects (EROs): LSP 1 follows the path made up of the interfaces { d, e, f, g, h, i} on nodes { LER A, LSR A, LSR B, LER B }.

LSP 2 follows the path made up of the interfaces { c, j, k, l } on nodes { LER A, LSR C, LER B }. Typically, the above interfaces would be recorded as IP addresses (e.g., d =—I use symbols just for simplicity. Selecting paths that optimize network resource utilization in advance of circuit creation is called traffic engineering. One of the Java patterns I’ll use illustrates TE.

Figure 1

Figure 1 Multisite enterprise using IP/MPLS service provider.

LSP 1 has also been configured to reserve bandwidth (in a process called QoS provisioning) along its path of 2Mbps (i.e., 2 million bits/second). This means that the real-time VoIP and video-over-IP traffic can be MPLS-encapsulated and pushed onto this path. LSP 1 terminates on LER B where any MPLS information is stripped from the packets. At this point, a normal IP lookup occurs, and the real-time traffic is forwarded to either the adjacent transit service provider or the branch office via CE2.

LSP 2 has no bandwidth resources reserved; it offers a Best Effort (or standard IP) QoS. This LSP is used to forward the SMTP (email) traffic across the core to LER B. Again, at LER B, the MPLS information is stripped away and normal IP lookup occurs. The traffic is then forwarded to CE Router 2 in the direction of the branch office site.

Figure 1 illustrates three different types of nodes: customer edge (CE), provider edge (PE), and provider core (P). CEs reside on the customer premises and can be basic IP routers. PEs reside at the edge or point of ingress of the provider network, and function as an on-ramp to the MPLS core. Ps are found inside the core and may be basic ATM/FR switches that are running MPLS protocols.

A major strength of MPLS is that it uses proven IP protocols to replace existing legacy technologies, such as ATM and Frame Relay. Network management (NM) is a key element of this evolution.

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.


Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.


If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.


This site is not directed to children under the age of 13.


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020