Introduction To ISDN, Part II
In the previous ISDN article, we looked at how and why one router dials another using ISDN. Just as important is knowing what keeps the link up once it is dialed.
Why? Because ISDN acts as a phone call between two routers, and it‚??s billed that way to your client. The two routers that are connected by this phone call may be located in different area codes, so now we‚??re talking about a long distance phone call.
If your ISDN link does not have a reason to disconnect, the connection could theoretically last for days or weeks before someone realizes what‚??s going on. This is particularly true when the ISDN link is used as a backup for another connection type, as is commonly the case with Frame Relay. When the Frame Relay goes down, the backup ISDN link comes up when the Frame Relay link comes back not billed for all that time.
To understand why an ISDN link stays up when it‚??s not needed, we have to understand why it stays up period. Cisco‚??s ISDN interfaces use the idle-timeout to determine when an ISDN link should be torn down. By default, this value is two minutes, and it also uses the concept of interesting traffic.
Once interesting traffic brings the link up, by default all traffic can cross the link. However, only interesting traffic resets the idle-timeout. If no interesting traffic crosses the link for two minutes, the idle-timer hits zero and the link comes down.
If the protocol running over the ISDN link is RIP version 2 or EIGRP, the most efficient way to prevent the routing updates from keeping the line up is expressly prohibiting their multicast routing update address in the access-list that is defining interesting traffic. Do not prevent them from crossing the link entirely, or the protocol obviously won‚??t work correctly.
With OSPF, Cisco offers the ip ospf demand-circuit interface-level command. The OSPF adjacency will form over the ISDN link, but once formed, the Hello packets will be suppressed. However, the adjacency will not be lost. A check of the adjacency table with show ip ospf adjacency will show the adjacency remains at Full, even though Hellos are no longer being sent across the link. The ISDN link can drop without the adjacency being lost. When the link is needed, the adjacency is still in place and data can be sent without waiting for OSPF to go through the usual steps of forming an adjacency.
This OSPF command is vital for Cisco certification candidates at every level, but is particularly important for CCNA candidates. Learn this command now, get used to the fact that the adjacency stays up even though Hellos are suppressed, and add this valuable command to your Cisco toolkit.
One myth about ISDN is that Cisco Discovery Packets keep an ISDN link up. CDP is a Cisco-proprietary protocol that runs between directly connected Cisco devices. There is a school of thought that CDP packets have to be disabled on a BRI interface in order to prevent the link from staying up or dialing when it's not really needed. I've worked with ISDN for years in the field and in the lab, and I've never seen CDP bring up an ISDN link. Try it yourself the next time you're working on a practice rack!
Chris Bryant, CCIE (TM) #12933, has been active in the Cisco certification community for years. He worked his way up from the CCNA to the CCIE, and knows what CCNA and CCNP candidates need to know to be effective on the job and in the exam room.
He is the owner of http://www.thebryantadvantage.com, where he teaches CCNA and CCNP courses to small groups of exam candidates, ensuring they each receive the individual attention they deserve. Classes are offered over the Internet and in person in select cities. Chris has custom-written the Study Guide and Lab Workbook used in each course - no third-party training materials or simulators are used.
You're invited to visit our site and check out our CCNA and CCNP courses and study aids, and to sign up for our weekly newsletter written personally by Chris. Chris is always glad to hear from Cisco certification candidates at email@example.com.
What Stands Behind The Software Description?
With thousands of web pages added to the Net every day, it's getting more and more frustrating both to submit the information to the attention of those, who are interested in it and to find the information one needs.
DVD Burning Tips
CD and DVD replication is a process that works by creating discs from scratch. Not to be confused with duplication (the act of burning information onto readymade, commercially-available blank CD-Rs and DVD-Rs), replication relies on the use of molds to produce actual discs that already contain digital data. It is the preferred and recommended mode of mass production for quantities in excess of 500 units.
Microsoft Great Plains: Large Scale Implementation
Microsoft Business Solutions Great Plains, Navision, Axapta, Solomon and CRM are coming up to satisfy ERP needs for large corporation, including multinationals. In this article we will be describing Microsoft Great Plains as the MRP platform, fitting to multiple industries and business niches: aerospace, defense, textile, pharmaceutical, healthcare, constructions, mining, services, distributions & logistics, wholesale & retail, public sector, chemicals, oil & gas, finance, brokerage, etc. We'll try to give you orientation and set realistic expectations if you are CIO for large publicly traded company and looking for reasonably budgeted solution.
Microsoft Great Plains Implementation: Verticals - Wholesale Order Entry center ? overview
Microsoft Business Solutions Great Plains has substantial market share and strong support by Microsoft on the US market. Currently we see the trend in the vertical markets when companies with custom-built accounting application, usually written on legacy platform are switching to standard and proven ERP solution and customize or tailor it to fit their vertical market requirements. We'll be publishing series of vertical articles: Logistics, Distribution Centers, Warehouse Management, Barcoding, Shipping/Receiving, eCommerce, EDI, Wholesale. Today we'll give you Wholesale tailoring scenario
Software Piracy - Global Increase
Pirated software is on the increase and now accounts for over one third of the software installed on the world's computers and it's cost the software industry a staggering, $28bn (£12bn) last year in lost revenues. That's the startling claim of the UK based, Business Software Alliance. Their annual survey of global software piracy shows that some 36% of software applications were illegally installed and being used during 2003.
Programming Language Migration Path
While I was preparing some personal background information for a potential client, I was reviewing all the programming languages that I have had experience with. I list languages that I'm most experienced with on my resume. However, it occured to me that if I was to list all the languages that I've worked with, then the client would become overwhelmed with the resume and just write me off as either a total bit head or looney toons. But as I reflected on all these different environments I realized how much fun I've had being involved with the software development industry, and that a lot of that fun has to do with the learning process. I think this is what makes a good programmer. Not just the ability to write code, or come up with a very creative application, but the ability to learn. Lets admit it! If a programmer doesn't have good learning skills, then the programmer is going to have a very short career.
Microsoft Great Plains Reporting ? Overview for Developer
Looks like Microsoft Great Plains becomes more and more popular, partly because of Microsoft muscles behind it.† Now it is targeted to the whole spectrum of horizontal and vertical market clientele.† Small companies use Small Business Manager (which is based on the same technology ? Great Plains Dexterity dictionary and runtime), Great Plains Standard on MSDE is for small to midsize clients, and then Great Plains serves the rest of the market up to big corporations.† There are several reporting tools available and you definitely need to know which one to use for different types of reports. If you are developer who is asked: how do we create report for Microsoft Great Plains ? read this and you will have the clues on where to look further. Great Plains Report Writer (ReportWriter) ? this is built-in reporting tool.† All the original report in Great Plains are written in ReportWriter.† ReportWriter itself is Dexterity module.† You should use this tool if you would like to modify existing Great Plains reports, such as Blank Invoice Form - here you can place your company logo, change the positioning, fonts, colors, etc.† ReportWriter will allow you also do new† reports - simple option† if you want to export all the records from one Great Plains table - use it.† New report, however doesn't have interface where you would enter parameters - so it is not useful for real custom reports.† Another limitation of ReportWriter - you can not do cross-modules report - when you need sales and purchasing info on the same report for example. FRx.† This is excellent tool when deal with financial reporting - it works on the General Ledger level (Balance sheet, P&L, Cash Flow Statement, etc.).† It also allows you to do multiple companies consolidation - when you do consolidated Balance Sheet (with inter-companies transactions elimination). Smart List - Export to Excel ? this is nice feature in Great Plains - you could create a list with simple criteria and then export it to Excel. Crystal Reports.† It gives you unlimited functionality.† Obviously flexibility requires you to know Great Plains table structure:† Launch Great Plains and go to Tools->Resource Description->Tables.† Find the table in the proper series.† If you are looking for the customers ? it should be RM00101 ? customer master file.† If you need historical Sales Order Processing documents ? they are in SOP30200 ? Sales History Header file, etc.† Create ODBC connection to GP Company database.† Use the same technique as when you create standard ODBC connection for GP workstation ? but change default database to targeted company database.† Create SQL Query to probe the data ? we always recommend tuning your query and see that you are getting adequate results ? in any case ? Crystal Report is just a nice tool to show the results of your query. Direct Web Publishing off Great Plains databases ? yes - it is easy now with Visual Studio.Net and you can hire good programmers.† This is good - Microsoft Business Solutions products: Great Plains, Solomon, Navision and Axapta will be integrated into so called Microsoft Business Portal - which will have web interface - you can get the idea if you look at Microsoft CRM web client - so direct web publishing is good taste. SQL Queries.† If you have SQL background - this is great field for you.† You know - with properly formatted SQL query you can realize simple EDI export/import for the integration with legacy systems. Happy designing!† if you want us to do the job - give us a call 1-866-528-0577! firstname.lastname@example.org
New Web-Based HR Tool is Max From NAS, Hannibal, and InfoLink
Three highly respected names in Human Resources have joined forces to provide companies with a revolutionary blend of services that make the hiring process more efficient and effective. The partnership joins three companies: NAS Recruitment Communications, a recognized leader in the specialized field of human resource communications, Hannibal, Inc., a software development firm specializing in recruiting automation solutions, and InfoLink Screening Services, Inc., a nationwide leader in employment background screening, drug testing and physical exam services.
Microsoft CRM and No-Frills Cadillacs
In today's business world it's all but impossible to escape Microsoft. Either you're using MS applications, developing your own, or negotiating your company's acquisition by this techno-behemoth. I must that the company is a daily part of my life (in fact I'm typing this article on MS Word). I've found however, that although Microsoft develops many versatile business software products, the company's 'one size-fits-all mentality goes only so far. I'm referring to the Microsoft CRM system. For you lay-people out there, CRM (customer relationship management) systems are designed to help you gather and interpret customer data in order to anticipate future customer purchasing demands and trends.
Microsoft Axapta, Navision or Great Plains: ERP Selection for Large Corporation
If you would like to pick something from Microsoft, or its ERP subdivision ? Microsoft Business Solutions, and in case of large public company, you should consider these three: Axapta, Navision or Great Plains. We are not talking about Solomon here, because it is recommended for project organization. You should probably be aware about specific product life cycle (or is it new or mature one on the market), database platform, average implementation cycle, typical customization requirements, rich vs. standard ERP functionality, etc. Also you should get comparison from relatively objective source, if you are asking to compare somebody, who implements and sells Great Plains ? more likely these people will try to prove that you need Great Plains and it is the best fit. On the other hand if you ask large consulting practice with regional offices to make comparison for you ? you should know that specific regional office might operate with maximum independence and promote, say Navision only.
SQL: Querying Microsoft Great Plains ? Overview for Database Administrator/Developer
Microsoft Great Plains Implementation for Midsize & Large Corporation: Lockbox Processing
Microsoft Great Plains is now targeting large and midsize businesses and being matured ERP has advanced, but still very simple in use modules and features: Lockbox Processing for Accounts Receivables, Customer/Vendor Consolidation, Multicurrency etc. We'll try to cover these features in the series of small articles to help decision maker and end user understand the feature and how does it work to make a decision to purchase additional nice modules. In our opinion large corporation, which had to use ERP with rich functionality in the past, doesn't have to do it in our new time. There are few reasons to switch to cheaper ERP, the most important are: database platform reliability improvement ? nowadays MS SQL Server does excellent job and has most of the former instability and maintenance issues resolved. The second reason ? MS Windows server is now close to be considered as a solid rock and you do not have to reboot it on the regular basis to fix all the types of "memory leaks", etc. OK, lets review Lockbox processing:
Is Your Family Protected?
When you think about Security, what do you think of? We all have one device or another to assist in keeping us safe. We have pad locks and security systems to safe guard our home, alarm systems to protect the equipment in our cars, parental controls on our cable TV and satellite accesses. We even have ways to protect our loved ones from computer invasions. But are we protected enough, are we using the best devices to combat the unwanted and dangerous intrusions, not to mention keeping our family from stumbling across those out on the internet? Let's face it, without the proper soft ware to protect your computer, you are at risk every time you connect to the internet. There are the viruses, the Trojans and unwanted spam, not to mention the chat rooms where millions fall victim of on-line predators, and let's not forget the #1 problem on the internet, pornography. You may be saying, but I have the best anti- spy ware money can buy and my internet service provides parental controls. Here's the underlying question: How effective are they? Statistics show that 95% of internet users don't have the adequate security to prevent attacks or control the content the computer user can access. The average computer is scanned by online intruders on average of 12 times a day. More and more victims are realizing the importance of these safety devices. The newest trend for identity theft is to steal information and cash out, out side of the country making it impossible to trace and leaving the victims with nothing to replace the funds. What do I do, you ask? Let me begin with the basics. There are four steps to take into consideration. 1. Evaluate- There are diagnostic tools to find and identify dangerous threats to your computer. These tools are as simple as popping into you computer and scanning your hard drive. Threats are then identified with the proper recommended course of action to take. 2. Eliminate- Once the threats have been identified the obvious next step is to eliminate. These security tools help scan, eliminate and block threatening spy ware, annoying ad ware and cookies, damaging worms and Trojan horses. 3. Protect- Set up a barrier around your computer. This will keep intruders out and create a fire wall. This is the most effective way to defend you against hackers and avoid identity theft. 4. Control- This final step will create a peace of mind for you, with the knowledge that you can avoid potentially dangerous web sites. You can block undesirable websites as well as avoid ones that try to download spy ware onto your computer. So what's the next course of action? Find a security device that will cover these four steps and protect you from all of these hazardous things. There are even programs that will do this and automatically update every month to ensure added safety and avoid any new unknown danger. My advice, find them, get them on your computer to avoid any heartache that could happen. The average cost for these programs, to completely cover you computer, vary from $40- $120 depending on the collection of software you use. The products that will automatically update usually run $5 - $10 a month to give you the essential idea of, get it and forget it. Too many times we forget to update our securities and fall victim of these malicious acts. Don't wait, don't become a victim before you take action. What is the price for your safety?
Twelve Things You Should Know to Save on Computer Software
Do you want to get quality software at a reasonable price? Whether you work at home or just need good software for your personal computer, you are faced with an almost endless selection of computer software. Sorting through the options can sometimes be a major task. However, if you want to get good, quality software there are several things that you can do that will save you money and headaches.
Best Practices In Choosing Network Monitoring Software
Blue Cross and Blue Shield of Hawaii (HMSA) found itself with a rapidly expanding network and data center. Our network devices, servers, and software were all growing in complexity and we knew that we would have to leverage technology to gain better control of our IT systems and network. In the past, we confronted the same dilemma that systems administrators in all IT organizations face: weighing the value of simple monitoring solutions versus expensive, feature-rich enterprise solutions that require labor intensive maintenance. We attempted to implement a large-scale system and network monitoring package from a major vendor but found the product was never fully implemented or adopted by the users because of its overbearing complexity. We then quickly implemented an inexpensive, low-end package that provided basic monitoring ? but lacked much of the deeper functionality our organization required, such as performance and application monitoring.
15 Questions to Ask Your Software Vendor
When making a decision to buy any piece of software there are a number of criteria typically evaluated. One of the most important elements in the decision process is the strength of the company that builds the software. In fact a survey of 19,000 customers has identified that company strength is the most important factor in choosing software, with the price of the software being the fifth most important element.
Where to Find Free Fleet Maintenance Software
Costs of fleet maintenance software can vary widely. It is generally expected that the fleet manager will look at the needs of the company to determine what software package is best suited for their particular needs. Depending upon the size of the company, number of vehicles to be maintained and services of the company, you may be able to locate free fleet management software for your needs.
Increase Office Efficiency With One Simple Tool
When you need a phone number, you do a quick search on the Internet and in a few seconds, you've got the information you need. And you probably receive a lot of contact information right inside the emails you receive every day. Both methods are by far more convenient than using those white or yellow-colored telephone directories.
Which Type of Shop Can Rely On A Home Built System?
eConnect: eCommerce Development for Microsoft Great Plains
Microsoft Business Solutions Great Plains has several options to enable web ordering. Traditionally Great Plains Dynamics/eEnterprise had eOrder ? this is ASP pages based ordering application, enabling you to place or retrieve your Sales Order Processing (SOP) Sales Orders over the web. There were several drawbacks however with eOrder. You should be the customer in Great Plains company database to be able placing the orders. Also if you were planning to customize eOrder ? you could only do cosmetic style changes only ? if you wanted to alter scripts on the ASP pages ? then you would have very serious eOrder upgrade issues. Upgrade simply wipes out your custom scripts and you had to reapply your customization to new version enriched ASP pages. Instead of following the way to move eOrder to ASPX or .Net platform ? MBS introduced eConnect, enabling web designer to "connect" eCommerce site to Great Plains backend. This is very elegant module and solution, however we are hearing a lot of complaints from developers on eConnect restrictions.
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