2010年8月30日 星期一

Setup DLNA/UPnP media server/control-point

DMS opensource
>> ushare
>> mediatomb
We need to install extra 2 libraries

because I install from RPM, so I download the following 2 rpm files
* id3lib-3.8.3-7.fc8.rf.i386.rpm
* js-1.60-4.fc8.i386.rpm
and the main mediatomb rpm
* mediatomb-0.9.1-1.fc7.i386.rpm
to install the UPnP AV media server

Be sure to disable the firewall rule blocking to allow the intial connections from DMP

>> How to run mediatomb
# mediatomb -i -a /root/share

DMP opensource
>> GeexBox
config tutorial

UPnP need the auto IP configurations, we can use avahi-autoipd to reach it
# avahi-autoipd -D eth1

DLNA cetificated devices include 3 main category
* Home Network Device (HND)
- Digital Media Server (DMS)
most popular usage or appliance that will implement
- Digital Media Player (DMP)

- Digital Media Render (DMR)

- Digital Media Controller (DMC)

- Digital Media Printer (DMPr)

* Mobile Handheld Device (MHD)

* Home Infrastructure Device (HID)

2010年8月26日 星期四

* telephone exchange
* telephone switch
Both telephone exchange or telephone switch are a system of electronic components that connects telephone calls. This process was manually before, nowadays it is an automatically process.

* Inside Plant
Telecomunication equipments that located in the telecompany building, such as DSLAM. In CATV, possible called CMTS.

* Outside Plant
Telecomunication equipments that located between main distribution frame (MDF) and User End instrument (or called Customer Premises Equipment).

Circuit switch versus Packet switch mechanism

Circuit switching
* Middle routers must presetup the link to transmit the data between two different DTEs
* Circuit-switched networks require dedicated point-to-point connections during calls.
* Data will arrive with constant bandwidth and at constant delay.
* example include Public Switch Telephone Network (PSTN)

Packet switching
* No need to presetup the link to transmit the data between two different DTEs. Data will go ahead from the source DTE to the destination DTE by using the store-and-forward mechanism in all the middle routers
* Pakcet-switched networks don't require dedicated point-to-point connections during calls.
* No predetermined path
* Data will not guarantee with constant bandwidth and constant delay. The communication may suffer from variable bit rate and delay, due to varying traffic load and packet queue lengths
* Include connection-oriented (known as virtual-circuit, described as stateful.) and connectionless (described as stateless)
* examples include TCP, X.25, Frame Relay, GPRS
* Virtual circuit switching technologies include ATM (use VCI/VPI in the cell header), MPLS

2010年8月25日 星期三

PPP protocol related

PPP (Point to Point Protocol)
* Can use to establish a direct connection between two network nodes
* This is a method for encapsulating multible protocol datagrams.

* It can provide connection authentication, transmission encryption privacy, and compression.
* A data link layer protocol

Q. How to setup a PPP connection?
- First of all, the Link Control Protocol (LCP) must be used to establish communications over a PPP link. Each link end sends LCP packets to configure, and test the data link connection. Subsequently, when the link is established, the peer may be verified by authentication.
- Once the link has been made, a Network Control Protocol (NCP) is used to establish and configure one or more network layer protocols that will be used for the link. Then datagrams from those network-layer protocols can then be sent over the link connection. The link will continue until closed.

* It is designed to supersede the Serial Line Internet Protocol (SLIP) and telephone company mandated standards (such as Link Access Protocol, Balanced (LAPB) in the X.25 protocol suite).
* It is designed to be conformable with other network layer protocols, including Internet Protocol (IP), Novell's Internetwork Packet Exchange (IPX), NBF and AppleTalk.

Q. Why does the EtherType contain PPP, 0x880B? Is PPP possible over Ethernet individually?

A Typical PPPoE Session flow

PPPoE packet format

PPPoE (Point to Point Protocol over Ethernet)
action flow as following steps
1. PPPoE client and PPPoE server interact with a series of packets include PADI/PADO/PADR/PADS. While the PPPoE client receive the PADS packet. PPPoE client will get the PPP session ID.
2. By using the received session ID. PPPoE client can start the PPP negotiation with the PPPoE server
3. After finished the ppp negotiation steps (about 20 ~ 30 packets). We get a ppp session.
4. Now we can process the application onto the ppp session.
5. While we finished the application executions. We can tear down the ppp session by sending PPP session-terminate request.

* Refer the following link
* It is mainly used by telephone companies. Client side user can "dial" to the server side router and gather a group of address for the following usage.
* The PPPoE has two distinct stages:
- PPPoE Discovery stage
a. Find the destination MAC address
b. Find the available session ID for the further usage
- PPP session stage

* EtherType define the PPPoE include the following value:
0x8863 PPPoE, PPP Over Ethernet (Discovery Stage).
0x8864 PPPoE, PPP Over Ethernet (PPP Session Stage).

Test items

Functional testing
Unit test, Module test
Conformance, sometimes we call "Interoperability"

Large volume testing
Capacity test, estimate the maximum volume of the DUT
Stress test, place the DUT in the high-pressure environment for a long period
Stability, place the DUT in the continuous great change environment

L2TPv3 experience

* A kind of Layer2 VPN that can carry multiprotocol on the ip-based backbone.
Multiprotocol include packet-switched traffic, such as frame relay, ATM and Ethernet, and time-division multiplexed traffic, such as voice and leased line.

MPLS tutorial

* MPLS can leverage the infrastructure of ATM network
* Use label substitution technology to route the packet from source to the destination
* The signaling method of ATM is complex. The MPLS method simplify the signaling method of ATM to IP-based request/response control protocol. Include
- UDP-Hello/UDP-Hello
- TCP-open/Initialization(s)
- Label request/Label mapping

different VPN skills

Layer2 VPN, include
IETF Martini draft
Circuit Cross Connect
Layer 2 Tunneling Protocol Version 2 (L2TPv2)
Layer 2 Tunneling Protocol Version 3 (L2TPv3)

Layer3 VPN
L2F (provided by Cisco?)

2010年8月24日 星期二


(Refer from the http://www.infocellar.com/cable-dsl/dte-vs-dce.htm)

Actually, DTE and DCE are different for the pin definitions of the connecting-interface. For the case of Ethernet scenario. In the DTE, port 1,2 are transmitted port, port 3,6 are received port. In the DCE, port 1,2 are received port, port 3,6 are transmitted port.
Cardinal Rule

DTE-DCE or DCE-DTE connections use Standard Ethernet Cable (straight-thru)
DTE-DTE or DCE-DCE connections use crossover Ethernet Cable (send/receive "cross over")
DCE/DTE refer to interfaces - not the actual device. A device can have both DCE and DTE ports. However, in general:

PC LAN cards (NIC - Network Interface Card) are DTE
Hub LAN ports are DCE
Hub Uplink Ports are DTE - it is a shared port with the last LAN port, but has the pinouts crossed
Cable Modem LAN port is DCE
Router LAN ports are DCE
Home Router WAN Ethernet ports are DTE

Almost all the WAN ports of CPE (Customer-premises equipment) device are DTE. All the LAN port of CPE devices are DCE.

曾興才牧師 - 20100808 - 我們渴望更多

曾興才牧師 - 20100808 - 我們渴望更多


1. 福音仍然是神的大能

2. 今天耶穌仍然醫治病人

3. 神仍然垂聽,應允我們的禱告
6:30~7:30 劉師母的禱告


4. 神仍然使用你來行神蹟奇事


2010年8月19日 星期四

資訊產業代工模式 - Some abbreviation of computing industrial

OEM - Original Equipment Manufacturing, current this model is less popular

ODM - Original Design Manufacturing, this model is work popolary, especially for the vendors in Taiwan

EMS - Electronics Manufacturing Service, Large scale information manufacturing, it was popoular and important in the recent decades.

CMMS - JDVM, Component Module Move Service - Join DeVelopment Manufacture. This is proposed by the Foxconn Technologies.

CMMS - JDSM, Component Module Move Service - Join DeSign Manufacture. This is proposed by the Foxconn Technologies.

什麼是電子專業代工(electronic manufacturing service, EMS或contract electronic manufacturing, CEM)

2010年報導 - 目前全球EMS產業營收第一名為鴻海(Foxconn), 第二名則為偉創力(Flextronics), 參考下列報導資訊

精實新聞 2010-07-28 15:45:32 記者 郭妍希 報導
科技市調機構iSuppli 27日發表研究報告指出,拜大客戶蘋果(Apple Inc.)營運快速成長之賜,2011年電子製造服務(EMS)大廠富士康(Foxconn Technology Group)營收佔整體EMS產業的比重料將超過50%,高於2009年的44.2%。

根據iSuppli調查,2010年第1季鴻海(2317)營收年增54.1%(季減19.7%)至171.47億美元,居全球EMS業者之冠,遠高於第2名偉創力(Flextronics International Ltd.)的59.4億美元。此外,鴻海Q1營收年增率也遠優於前10大EMS廠商的營收平均年增率27.5%。

Information from http://www.emsnow.com/spps/sitepage.cfm?catid=84
EMS ranking 2007
1. Foxconn
2. Flextronics
3. Jabil
4. Sanmina-SCI
5. Celestica

ODM ranking 2007
1. Quanta
2. Asustek
3. Compal
4. Wistron
5. TPV

2010年8月18日 星期三



EPS 選股網站

2010年8月15日 星期日


精實新聞 2010-06-11 19:51:45 記者 陳祈儒 報導


鄭炎為表示,仲琦大陸的Cable產線僅4條產線,在台商近期的調薪效益下,並不想增加更多的生產線與員工,以目前的訂單量其實來應要8條才夠,若再加上歐美等地市場的新接訂單,評估更要有11條產線才夠,因此目前公司已透過外包方式生產。他說,今年DOCSIS 3.0已逐漸替換成DOCSIS 2.0產品,而2011年也將全部進入3.0的換機潮。



由於仲琦在韓國、日本、北美與歐洲有DOCSIS 3.0的換機潮帶動,而且中國「三網合一」確定由廣電總局主導IPTV頻道,且讓中國當地的有線電視業者投入寬頻服務、語音服務等,讓中國市場在Cable 2.0需求會被激發上來,加上仲琦的SI系統部門接單穩定,較去年成長10%以上,因此法人也預估,仲琦今年整體營收將挑戰58~60億元,較去年成長逾55~58%,每股稅後盈餘將突破2元,較去年的1.08元成長一倍。

ISP deployment scenarios

Comparison of different internet access equipments in the different network system
Server-side-router (BRAS) - IP network, packet switched network - Cable modem termination system (CMTS)(head end) - Cable network (coaxial cable/RF, TDM, circuit switched network, Last Mile) - Cablem Modem (CPE) - SOHO Router

Server-side-router (BRAS) - IP network, packet switched network - IP DSLAM (head end, act like a network switch, Layer2 Equipment) - DSL network (Twisted Pair, circuit switched network, PPPoEoA or PPPoA protocol, Last Mile) - xDSL Modem (CPE) - IP network SOHO Router


DSLAM - Digital Subscriber Line Access Multiplixer

BRAS - Broadband Remote Access Server
A broadband remote access server (BRAS, B-RAS or BBRAS) routes traffic to and from the digital subscriber line access multiplexers (DSLAM) on an Internet service provider's (ISP) network.
Traditionally the BRAS will receive ATM cells/packets from ATM-DSLAM and then extract IP packets to the IP-network. In the decades, the ATM-DSLAM was changed to IP-DSLAM in a growing trend. So the BRAS will receive IP packets from IP-DSLAM nowadays. The result is from IP-DSLAM, it's a pure IP network anymore.
In the BRAS, ISP can do the policy management (Firewall), quality of service (QoS), AAA (accounting, authentication, authorization).

2010年8月10日 星期二

Telnet 輸入中文的好幫手 PieTTY

在一些BBS (如台大PP)或是其他telnet需要輸入中文時,putty都會出現亂碼,這時就要利用PieTTY這支精巧又好用的程式啦!

PieTTY 的特色

PieTTY 0.3 系列是修改自 PuTTY 0.57/0.58 的版本,以穩定與修正為主。 主要的特色有: screenshot

* 簡單易用的界面(中英文合一)。 主要的功能都可從選單存取
* 完全相容於傳統 PuTTY,之前的設定全部可直接使用
* 更強的連線整合管理(session management), 自動儲存設定
* 高度可自訂化(customizable)的視窗顯示效果
* 完整而方便切換的多國語言支援
* 半透明顯示(多種顯示引擎以配合各種硬體配備與視窗立體陰影,配合無框顯示模式效果奇佳 (0.3.27)
* 支援 ssh:// 式的呼叫,可整合系統設定為 ssh:// 與 telnet:// 處理程式(0.3.27)
* href screenshot對於各種網址 URL 可直接點選開啟,還有各種可選用的視覺效果
* 支援拖曳檔案 (Drag-n-drop) 即可 SCP 上傳

對於非英語系字元, PieTTY 特別加強的部份有:

* 可使用英文等其它字型,而且不用設定字元集(CHARSET) (傳統 PuTTY 則一定要設定正確才行)
* 在非 UTF8 模式下 PieTTY 的游標也能正確顯示 (傳統 PuTTY 會破壞游標上的多位元字元組如Big5中文)
* 重繪螢幕完全不閃動 (PuTTY 在非 UTF8 會閃)

對台灣 Big5 及 BBS 環境有更多的加強功能:

* 內建 Big5-2003 + 中國海字集、 相容Unicode補完計畫2.40版字碼表,免裝 Unicode 補完即可正常剪貼或輸入日文等(0.3.27) screenshot
* 內建簡單的漢字(簡繁)轉換,方便閱讀(0.3.27)
* 支援一字雙色的ANSI碼 (台灣 BBS 特有文化)
* 複製文字時可自動將屬性顏色以 ANSI 碼或 IRC 形式加入(0.3.27), BBS 與 IRC 互貼彩色不是夢!