UDLD (Unidirectional Link Detection) is Cisco proprietary extension for detecting a mis-configured link. The idea behind it is pretty strighforward – allow two switches to verify if they can both send and receive data on a point-to-point connection.

Consider a network with two switches, A and B connected by two links: “A=B”. Naturally, if “A” is the root of spanning tree, one of the ports on “B” will be blocking, constantly receiving BPDUs from “A”. If this link would turn uni-directional and “B” would start missing those BPDUs, the port will eventually unblock, forming a loop betwen “A” and “B”.

Note that the problem with unidirectional links usually occurs on fiber-optical connections and is not common on UTP (wired) connections, where link pulses are used to monitor the connection integrity.

The confusion about UDLD is that Cisco provides quite unclear description of the feature operations be it on CatOS or IOS platform. So here is a short overview of how UDLD works.

1) Both UDLD peers (switches) discover each other by exchanging special frames sent to well-known MAC address 01:00:0C:CC:CC:CC. (Naturally, those frames are only understood by Cisco switches). Each switch sends it’s own device ID along with the originator port ID and timeout value to it’s peer. Additionally, a switch echoes back the ID of it’s neighbor (if the switch does see the neighbor). Since some versions of CatOS and IOS you can change UDLD timers globally.

2) If no echo frame with our ID has been seen from the peer for a certain amount of time, the port is suspected to be unidirectional. What happens next depends on UDLD mode of operations.

3) In “Normal” mode, if the physical state of port (as reported by Layer 1) is still up, UDLD marks this port as “Undetermined”, but does NOT shut down or disable the port, which continues to operate under it’s current STP status. This mode of operations is informational and potentially less disruptive (though it does not prevent STP loops). You can review the “undetermined” ports using CLI show commands when troubleshooting the STP issues though.

4) If UDLD is set to “Agressive” mode, once the switch loses it’s neighbor it actively tries to re-establish the relationship by sending a UDLD frame 8 times every 1 second (surpisingly this coincides with TCP keepalives retry values used by FCIP on Cisco MDS storage switches . If the neighbor does not respond after that, port is considered to be unidirectional and brought to “Errdisable” state. (Note that you can configure “errdisable recovery” to make switch automatically recover from such issues)

5) UDLD “Aggressive” will only brings link to errdisable state when it detects “Bidirectional” to “Unidirectional” state transition. In order for a link to become “Bidirectional”, UDLD process should first hear an echo packet with it’s own ID from a peer on the other side. This prevents link from becoming errdisabled when you configure “Aggressive” mode just on one side. The UDLD state of such link will be “Unknown”.

6) UDLD “Aggressive” inteoperates with UDLD “Normal” on the other side of a link. This type of configuration means that just one side of the link will be errdisabled once “Unidirectional” condition has been detected. To finish the overview, recall that UDLD is designed to be a helper for STP. Therefore UDLD should be able to detect an unidirectional link before STP would unblock the port due to missed BPDUs. Thus, when you configure UDLD timers, make sure your values are set so that unidirectional link is detected before “STP MaxAge + 2xForwardDelay” expires (by default it’s 20+2×15 seconds, though who uses the classic STP with defaults nowdays

Perusing the Twitterscape I came upon an interesting blog post about how libraries need to cater to teens in order to survive the Information Age which is rapidly picking up speed. A commentator had a different viewpoint:

“Why are newspapers in trouble? People stopped supporting them (buying them) as the newspaper’s content became more freely available online. The more newspapers’ revenues dropped, the more staff they had to cut, the less original content appeared in the newspaper, and the more people decided that a subscription to the actual newspaper was unnecessary.
I see the same thing happening with libraries, as non-users believe everything we provide is available online or soon will be. If we position ourselves primarily as a provider of resources and Internet access to low-income populations, we run the risk of any social service agency of being the first onto the budget chopping block. Middle- and high-income populations don’t need libraries on an economic basis.
I think libraries need to position themselves as educational institutions, centers of lifelong learning for all ages and incomes, populated with staff that is knowledgeable and quick, so that even non-library users will believe that libraries are worthy of public support. I think that’s the most effective way of winning support for teen services, as well as libraries in general. Libraries provide more than books and Internet access, and education takes place outside of school buildings. We need to get that message out.”

I feel that this touches on a very important point: libraries have never been teen hanging-out locations, so why would we start now? Libraries are information repositories, not Net Cafés. Yes, information is more readily available on the Internet than it ever has been. Yet as any school teacher will tell you, not all of it is good. Wikipedia, though good, is not focused toward academia. Librarians are trained to find relevant information 100% FREE of charge to anyone who asks them. So market that. Make everyone realize that the library exists. Increase accessibility to holdings and reference librarians. Speak the teenage language without marketing the library as something it’s not.

Links for everything

Inspiratiion

http://petespacket.com/ The Main Inspiration for this blog

Techie

http://www.rfc-editor.org/ Every RFC You ever wanted

Setiap kali terhubung ke internet, sebuah komputer akan mendapatkan serangkaian angka yang menjadi identitas alamat komputer itu. Jika menggunakan Microsoft Windows ketika komputer terhubung ke internet, coba aktifkan Command Promt dan ketikkan perintah ipconfig. Maka akan kelihatan IP Address, Subnet Mask dan Default Gateway.

Komputer dari indonesia biasanya berangka depan 202 berdasarkan pembagian wilayah alamat IP. Angka-angka lainnya identik dengan identitas perusahaan penyedia jasa internet (ISP, internet Service Provider) dan pelanggannya. Jadi, dari sebuah alamat IP, pelacakan bisa dilakukan sampai ke lokasi komputer pemakai internet. Dari alamat IP saja, setidaknya para penyelidik bisa tahu apakah sebuah komputer berada di medan, pekanbaru, atau kota-kota lainnya. Berdasarkan alamat IP juga, lewat kerjasama dengan perusahaan penyedia jasa internet, penyelidik bahkan bisa tahu pelanggan ISP yang pernah menggunakan alamat IP tertentu. Cara yang bisa untuk menyembunyikan alamat IP aslinya adalah dengan memanfaatkan akses kesebuah proxy server.

Proxy Server menjadi semacam perantara yang menghubungkan komputer seseorang dengan internet. Banyak perusahaan atau lembaga-lembaga yang menyediakan proxy server untuk memastikan keamanan, mengendalikan administrasi dan menyediakan layanan caching yang bisa mempertinggi laju kecepatan akses ke sebuah sumber internet. Bahkan lebih dari sekedar perantara, sebuah proxy server juga mewujud sebagai perwakilan dari sebuah komputer yang terhubung ke internet.

Salah satu contoh penyedia daftar alamat proxy server gratis itu bisa diakses di www.nntime.com. Para carder lebih suka memilih proxy server yang berlokasi di negara-negara yang tidak masuk dalam daftar hitam (black list) sebagai negara asal para pelaku kejahatan internet, atau negara yang sesuai dengan negara pemilik kredit yang akan dipakainya dalam beroperasi.

Untuk mengubah setting koneksi internet menggunakan browser Microsoft Internet explorer sebagai berikut:

Tools, pilih Internet Options, pilih tab Connection, menekan tombol LAN setting, pilih use a proxy server for your LAN dan isikan alamat proxy server yang sudah diperoleh tadi dan mengaktifkan pilihan Bypass proxy server for local address, menekan tombol Advance sambil mengaktifkan opsi Use the same proxy server for all protocol, lalu menekan semua tombol OK.

Ada beberapa asumsi yang menjadi alasan untuk menguji proxy server yang dipakai sebelum mulai melakukan carding. Pertama, proxy server yang diperoleh belum tentu dikonfigurasi untuk menyembunyikan alamat IP. Kedua, proxy server yang dipakai belum tentu aktif pada waktu akan menjalankan operasinya.

Stay Invisible (http://www.stayinvisible.com) adalah layanan pengujian alamat IP dan proxy server yang tersedia di internet. Situs web ini sebenarnya merupakan sumber informasi yang menyokong isu privasi, keamanan dan berinternet secara anonim. Terdapat satu menu bertajuk Test Your IP, dengan mengklik menu itu situs web ini mencoba mendeteksi alamat IP dan proxy pengaksesnya. www.showmyip.com layanan sejenis yang memberikan informasi tentang kota tempat si pengakses. Jika alamat IP asli tidak terdeteksi, maka segera menjalankan aksi carding.

Bapak Setyo adalah salah satu staf pengajar di STMIK Balikpapan, yang memiliki personal website http://www.snpages.info, sang bapak yang dapat dan mau berdikusi dengan siapa saja untuk berbagi pengalaman dan pemikiran maupun pengetahuan. Ketertarikan saya terhadap AI khususnya Jaringan Syaraf Tiruan dan Pengolahan cita membuat saya terus berselancar dan berselancar sampi ketemu websitenya si bapak. Banyak hal yang bisa di pelajari dari websitenya si bapak khususnya tentang JST dan Pengolahan Citra. Jurnal-jurnal setra dukungan Source Codenya yang diberikan si bapak untuk bisa di kembangkan buat teman-teman yang lagi kebingungan dalam mempelajari JST dan Pengolahan Citra.

In my previous post last month I was telling my fellow agents about the tremendous possibilities in the field of Medical Assistant courses. I got an overwhelming response from my previous post and there were so many queries from the agents as well as prospective students which needs to be addressed in a proper manner. Most of the questions were about the nature of medical assistant occupation and duties conducted by an average medical assistant.

Study Abroad Commission Junction contacted St. Augustine School of Medical Assistants, one of the leading medical assistant school in US for few unanswered questions. Good guy at St. Augustine School of Medical Assistants revealed some unknown facts about this high-demand occupation.

Medical assistants perform administrative and clinical tasks to keep the offices of physicians, podiatrists, chiropractors, and other health practitioners running smoothly. They should not be confused with
physician assistats, who examine, diagnose, and treat patients under the
direct supervision of a physician. The duties of medcal assistants vary from office to office, depending on the location and size of the practice and the
practitioner’s specialty.

In small practices, medical assistants usually are generalists, handiling both
administrative and clinical duties and reporting directly to an office
manager, physician, or other health practitioner.

Those in large practices tend to specialize in a particular area, under the
supervision of department administrators. medical assistants perform
many administrative duties, including answering telephones, greeting
patients, updating and filing patients’ medical records, filling out insurance forms, handling correspondence, scheduling appointments, arranging for
hospital admission and laboratory services, and handling billing and bookkeeping. Clinical duties vary according to State law and include taking medical hostories and recording vital signs, explaining treatment procedures to patients, preparing patients for examination, and assisting the physician during the examination.

Medical assistants collect and prepare laboratory specimens or perform basic laboratory tests on the premises, dispose of contaminated supplies, and sterilize medical instruments. They instruct patients about medications
and special diets, prepare and administer medications as directed by a physician, authorize drug refills as directed, telephone prescriptions to a
pharmacy, draw blood, prepare patients for x-rays, take electrocardiograms, remove sutures and chage dressings.

Medical assitants also may arrange examinng room instruments and equipment, purchase and maintain supplies and equipments.

One of my client wrote an email from Maryland yesterday. She had all praise for the choice of course I suggested her when she first came to my office seven months back.

She writes, “Medical assisting program at my ultrasound tech school has been a great course for me as I have worked side by side with a ob/gyn doctor for over few months now for my ultrasound tech training.  Everything I have learned has been through him but this medical assistant course has offered me so much I have taken my time and studied very hard and have already put this in advantage to my every day work. I can now spit out medical terms to the doctor with no problem and even know what needs to be done most of the time before he even write orders, Thank you so much for suggesting medical assistant program to me. It has helped me very much and the text book will be a learning tool that I am sure I will refer to more then once in a while I cant say enough great about medical assistant program.  Thanks again.”

Well, such emails are routine in our business but this particular mail struck me. I was aware of the vast career opportunities this course offers but I never knew that Medical Assistant is in fact proving as Backbone of the Health care Industry.

I contacted many study abroad consultants in China, South Korea, India and Singapore and all of them responded with the similar reply, “We are selling more than 20 (some even 35) courses per month, what about you?” So the industry is very well aware of this emerging trend.

The Medical Assistant profession is experiencing tremendous growth also because of the increasing number of senior citizens as well as the insurance industry’s greater demand for preventative medical care. The number of jobs for certified medical assistants to aid nurses, doctors, and primary caregivers with various patient, clinical, and administrative tasks is likely to grow 30.3% by 2014, industry sources indicates. So what are you waiting for fellow agents and consultants. Here are the few resources to help you out more regarding the different courses available for you to sell. Happy Selling!

Most of the study abroad agents and overseas study consultants are facing problems when it comes to providing assistance to their client students in preparing essays for University admissions. Most of the times our clients get stressful in working on the writing assignment given by various campuses they are seeking admissions in. You need an Essay Writing Service to help your client in creating a Custom Term Paper so that they are able to fulfill their assignments to meet the deadline.

After long research and talking with many students and fellow agents in the Study Abroad Industry we’ve reached on conclusion that one of the best custom writing companies existing on the world wide web is Master Papers, which is a global leader in custom essay writing and Dissertation Help for students.

Contribution of  Master Papers in helping Phd. students on their Thesis Topics is immense and most of my students clients who have had taken up their services in preparing their thesis are very much satisfied with the efforts of  their professional writers.

Master Papers has a fleet of experienced 500 specialists that specializes in helping students with their term papers and research papers by producing professional writing services. Master Papers banks on superior quality, creativity and originality for each essay writing assignments that they produce and deliver each assignment on time to those who have requested their services. For each paper that they write, immaculate attention is paid on the rules and instructions given from the customer. Combined with an amazing and extensive vocabulary and creative writing, the end result is a guarantee that pleases Master Papers’ clients.

gage = 18st 4.5 inch

us 5

co 96st

Row 1: kfb, k2, m1, k1, pm, k1, m1, k12, m1, k1, pm, k1, m1, k56, m1, k1, pm, k1, m1, k12, m1, k1, pm, k1, m1, k2, kfb

Row2: knit all stitches

Row3: repeat row 1

Row 4: knit all stitches

Continue until you have 108 st on back pannel, slip sleeve stitches onto waste yarn

Knit all stitches join front to back, slip 2 stitches between these pannels to create false seam.

CO 8 stitches at begining of next 2 rows.

Knit for 2 inches.

Row 1: [K31 st, kfb] repeat 8 times 256 st

Row 2: Knit all stitches

Repeat rows 1 & 2 three times

Continue in garter stitch for 16 inches from arm hole. BO loosely all stitches

Work in garter stitch kfb every 4th row until piece measurues 12 inches

Sleeve Lace

Row1: [K2tog] 3 times, [k1, yo] 6 times, repeat till last 6 stitches [K2tog] 3 times

Row 2: knit all stitches

Row 3: knit all stitches

Row 4: purl all stitches

repeat rows 1-4 till length reaches 12 inches