Data Transfer Speeds

A common question most of my students ask, and just recently, by someone who is not my student, but a student of the school where I used to teach asked this: What is the speed of DSL? What is the speed of a dial-up modem? And all other speed questions. I decided to place this all into one table compiled from all these notes I have. The table below may not be complete, and if ever you know some kind of data transfer I have not metioned below, please add a comment to this page so I can add this to the table.

Data Transfer Type	Speed
POTS Plain Old Telephone System	28.8 kbps
Switched 56 Switched 56	56 kbps
SMDS Switched Multimegabit Data Service	56 kbps to 34 Mbps
ISDN Integrated Services Digital Network	64 kbps
DS0 Digital Signal Level 0	64 kbps
ISDN Dual ISDN Dual Channel	128 kbps
LocalTalk LocalTalk	230.4 kbps
ADSL Asymmetric Digital Subscriber Line	640 kbps upstream, 6 Mbps downstream
Bluetooth Bluetooth wireless PAN (2.4 GHz band)	720 kbps
IEEE 802.11 Institute of Electrical and Electronic Engineers 802.11 wireless (2.4 GHz band)	2 Mbps
Cable Cable Modem	1 Mbps
DS1 Digital Signal Level 1	1.544 Mbps
T1 Terrestrial 1	1.544 Mbps
PCS Personal Communication System Wireless	2 Mbps
E1 European Digital Signal Level 1	2.048 Mbps
DS2 Digital Signal Level 2	6.312 Mbps
T2 Terrestrial 2	6.312 Mbps
E2 European Digital Signal Level 2	8.448 Mbps
10Base-T 10Base-T Ethernet	10 Mbps
IEEE 802.11b Institute of Electrical and Electronic Engineers 802.11b wireless Wi-Fi(2.4 GHz band)	11 Mbps
USB Universal Serial Bus	12 Mbps
U-NII U-NII Wireless	20 Mbps to 24 Mbps
ATM Asynchronous Transfer Mode	25.6 Mbps to 155.52 Mbps
E3 European Digital Signal Level 3	34.368 Mbps
SCSI-1 Small Computer System Interface 1	40 Mbps (5 MBps)
DS3 Digital Signal Level 3	44.736 Mbps
T3 Terrestrial 3	44.736 Mbps
OC1 Optical Carrier Level 1 - Synchronous Optical Network (SONET)	51.84 Mbps
STS-1 Synchroous Transport Signal 1 - Synchronous Optical Network (SONET)	51.84 Mbps
IEEE 802.11a Institute of Electrical and Electronic Engineers 802.11a wireless WLAN(5 GHz band)	54 Mbps
IEEE 802.11g Institute of Electrical and Electronic Engineers 802.11g wireless WLAN(2.4 GHz band)	54 Mbps / 11 Mbps
Fast SCSI Fast Small Computer System Interface	80 Mbps (10 MBps)
100Base-T 100Base-T Ethernet (Fast Ethernet)	100 Mbps
OC3 Optical Carrier Level 3 - Synchronous Optical Network (SONET)	155.52 Mbps
STM1 Synchroous Transport Mode 1	155.52 Mbps
Fast Wide SCSI Fast Wide Small Computer System Interface	160 Mbps (20 MBps)
Ultra SCSI Ultra Small Computer System Interface	160 Mbps (20 MBps)
DS4 Digital Signal Level 4	274.176 Mbps
T4 Terrestrial 4	274.176 Mbps
Wide Ultra SCSI Wide Ultra Small Computer System Interface	320 Mbps (40 MBps)
FireWire Institute of Electrical and Electronic Engineers 1394A	400 Mbps
OC9 Optical Carrier Level 9 - Synchronous Optical Network (SONET)	466.56 Mbps
STM3 Synchroous Transport Mode 3	466.56 Mbps
USB 2.0 Universal Serial Bus 2.0	480 Mbps
OC12 Optical Carrier Level 12 - Synchronous Optical Network (SONET)	622.08 Mbps
STM4 Synchroous Transport Mode 4	622.08 Mbps
Wide Ultra2 SCSI Wide Ultra2 Small Computer System Interface	640 (80 MBps)
FireWire 800 Institute of Electrical and Electronic Engineers 1394B	800 Mbps
ATA/100 Parallel Advance Transfer Adapter/100 Parallel	800 Mbps (100 MBps)
Gigabit Ethernet Gigabit Ethernet	1 Gbps
OC24 Optical Carrier Level 24 - Synchronous Optical Network (SONET)	1.244 Gbps
STM8 Synchroous Transport Mode 8	1.244 Gbps
Ultra 160 SCSI Ultra 160 Small Computer System Interface	1.280 Gbps (160 MBps)
Ultra 3 SCSI Ultra 3 Small Computer System Interface	1.280 Gbps (160 MBps)
Ultra Serial ATA 1500 Ultra Serial Advance Transfer Adapter 1500	1.5 Gbps
OC36 Optical Carrier Level 36 - Synchronous Optical Network (SONET)	1.866 Gbps
STM12 Synchroous Transport Mode 12	1.866 Gbps
OC48 Optical Carrier Level 48 - Synchronous Optical Network (SONET)	2.488 Gbps
STM16 Synchroous Transport Mode 16	2.488 Gbps
Ultra 320 SCSI Ultra 320 Small Computer System Interface	2.560 Gbps (320 MBps)
OC96 Optical Carrier Level 96 - Synchronous Optical Network (SONET)	4.976 Gbps
STM32 Synchroous Transport Mode 32	4.976 Gbps
OC192 Optical Carrier Level 192 - Synchronous Optical Network (SONET)	9.953 Gbps
STM64 Synchroous Transport Mode 64	9.953 Gbps
10G Ethernet Institute of Electrical and Electronic Engineers 802.3ae	10 Gbps
OC255 Optical Carrier Level 255 - Synchronous Optical Network (SONET)	13.271 Gbps
OC768 Optical Carrier Level 768 - Synchronous Optical Network (SONET)	40 Gbps

First Full CSS and SEO Website to the Max Ever!!!

I myself am new to what I am promoting. For the past few days I was starting to learn more and more about CSS and SEO. At work at Einstein Industries I have been applying a few things here and there. But I have not used it 100%.

I have been working on a website, but it is not yet completely done. But is starting it using full CSS, SEO and PHP with 2 major goals in mind...

1. Modularity and scalability for fast and easy website updating.
2. Totally optimized website for SEO.

And so far I'm happy on how I am doing. The website is for the San Diego Taekwondo Association and for HTML coders there, you can check out the site and see the source code having no table tags. Easier to maintain, smaller disk space and faster page loading. Actually there are a lot more underground secrets why this style of page building is better than the conventional table tags and transparent gif spacers, but then again, they are secrets. :P

CSS is the Future

I can say I grew up in web designing since I learned how to do this since 1996. My career in web designing and web development all started with basic HTML. HTML was still in it's early stages when I started, and the W3C was still with the HTML 2.0 standard and was working on HTML 3.0. Tags and attributes were limited then. And Microsoft Internet Explorer was inventing tags that only Internet Explorer knew and so was Netscape Navigator was also inventing tags that one Netscape knew.

Some tags became standard, others not, some tags are starting to be obsolete and were being removed from the standards made by the W3C but the major browsers still seem to know many of the old tags.

The additional languages and plug-ins started to come out since HTML is limited. Some are still used today, some died in history. Today, HTML in it's pure code form is widely used with JavaScript and CSS (Cascading Style Sheets). We're not talking about plug-ins like Flash, Quicktime, MediaPlayer, Real Player, Java, or the server-side programming languages. We're just talking about HTML code and everything you type in it that will run without any other plug-in and the browser will simply understand it client-side.

When CSS came out and I even actually bought a book about CSS in it's early stages, I just read it cover to cover and said to myself, that's it? CSS is easy and why do I need it if I can do things with HTML alone?

Although I used CSS early, I used it only for links. Since there is really no way to take out the underline in text links using HTML alone. And I found it cumbersome in it's early stages figuring out how things should be done in Internet Explorer and how it should be done in Netscape.

Today CSS has evolved into the most powerful tools in web design. Once mastered you will totally forget HTML's table tags and frame tags, even iframes. Now this article is not a full fledged CSS tutorial, sorry if that's what you are expecting. Actually this article is intended for people who have been playing with HTML already since they are the main people that will appreciate all of this. What I am going to mention though is how to optimize CSS and the advantages of it and why I am starting to shift to use this so much.

• A basic is as much as possible, place all styles in one CSS file and link the HTML page to it. I guess many CSS users already know this. And the advantages, many of you also know, for easy updating, change the CSS file and you change everything. If you change the font size in the CSS file, the whole website is affected.
• Cleaner code without table tags. Simply using div tags and height, width, margins and padding in CSS and you're ready to go. Having div containers help a lot too. Background images in divs even have the option to be tiled or not. No need to use transparent spacer graphics as well to position things around.
• Controlled padding in the p, li and heading tags. P, li and heading have large paddings and to be able to control them would be great.
• Byebye to frames. Like tables, code just get so many, real long code, especially in nesting them. With CSS, it is way more simpler. Faster to implement, shorter code, more precise and accurate in positioning and sizes.
• Cascade whatever you can cascade. I never really understood this before, I used CSS, but it was like I was only using the "SS" without the "C". Consolidate your elements as well in CSS file. Using it and doing it will get you a better picture of the advantages of this. Minimize ids and classes as much as possible.
• Learn how to float div boxes and this makes shopping carts and picture galleries a lot more easier to implement, than having tables with repeating td tags and numerous computations and counting to determining when tr tags must come out.

Right now, if you do not know CSS, everything written here may sound nonsense. But when the days comes and you do get into CSS, remember all the tips I said above. If you know CSS but still have no idea what the real advantage is, it is a lot more easier to understand why, when you see it yourself. I hope I have time soon to type in a few CSS tutorials next time.

I'd like to thank everyone at Einstein Industries, they are giving new meaning to CSS as how the way I understood it. To my students, experience is still the best teacher. I read all about CSS before, I was even teaching it in school, but the real advantage of it, I just saw it now with the help of other people who use CSS too. CSS is the future of web design.