CMMI

CMMI (Capability Maturity Model Integration) is a standardized process improvement approach in order to achieve and maintain performance goals in an organization. CMMI is registered in the U.S. Patent and Trademark Office by Carnegie Mellon University. The scope of a CMMI would vary from requirements engineering to areas such as decision management, performance measurements, planning, risk management etc. Wikipedia has classified those into three broad areas.

1. Product and service development — CMMI for Development (CMMI-DEV)
2. Service establishment, management, and delivery — CMMI for Services (CMMI-SVC)
3. Product and service acquisition — CMMI for Acquisition (CMMI-ACQ)

Imposing a CMMI process can be focused to a small work group or to the entire organization upon its pre-defined KPIs. When it comes to history of CMMI, it evolved from Software Capability Maturity Model and in 2002 CMMI Version 1.1 has been released. Version 1.2 came in to the picture in August 2006 and in November 2010 version 1.3 has been introduced. CMMI defines five maturity levels in development and services.

Level 1 – Initial: no predictability in schedule, budget, scope or quality, reactive

Level 2 – Managed: specific implementation of a process focusing each project, reactive

Level 3 – Defined: Proactive, processes characterized for the organization

Level 4 – Quantitatively managed: projects and processes are quantitatively managed and controlled

Level 5 – Optimizing: This is where the organization continues what they have gained up to level 4, hence achieve continuous improvements

The main advantage any organization can derive by successfully implementing CMMI is the institutionalization practices. In simple terms, once you implemented CMMI, it will lead the organization to maintain generic practices (as it will be defined, documented and well-understood by every stakeholder), which can be implemented to any project or process and the changes will be observable.

Colombo Stock Exchange (CSE)

This blog post basically focuses on what are the general information that any person might need to know when you are dealing with CSE. Motive behind this is all the time I hear bits and pieces of CSE and its transaction processes but never was able to get the full picture. All the information provided in this post have been extracted from www.cse.lk as it is the primary source that we can learn about it. Hope this helps out to clear the clouds.

1. Only the listed companies (listed in CSE Indexes) can go for public share offerings. This means if a company willing to offer shares to public investors, first these companies need to be in compliance with an Exchange's set of listing rules such as previous profit records, issued/paid up capital etc. in order to be admitted to the official list. There are two price indexes in CSE viz. All Share Price Index (ASI) and Milanka Price Index (MPI)

2. There are two types of share offerings.

A). From New share issue (Primary market) – This is called “IPO (Initial Public Offering)”. In primary market stocks (also called ‘security’) has to by directly from Issuer Company.

B). on ordinary market (Through stock brokers) – Here investors can buy or sell shares from or to another investor. This can take place only after an IPO in primary market.

3. CDS (Pvt.) Ltd (Central Depository System) – Fully owned subsidiary of CSE which perform functions of Clearing, Settlement and Registration from the Stock Exchange on behalf of CSE. Every investor has to register (open an account) at CDS via a preferred stock broker and will be given a unique account number that will correspond to each and every detail/transaction related to that particular investor. CDS account enables investors to participate in paperless trading on the Colombo Stock Exchange. CDS account will be maintained in double-entry book-keeping format and will be updated on real time.

4. Stock brokers – Authorized entities to buy and sell shares on behalf of investors. The CSE has 15 member firms and 9 trading member firms authorized to buy and sell shares at the moment.

5. Buy & Sell shares through a stock broker –

A). Investor must first find yourself a stockbroker /custodian bank and open a CDS account through that participant(Participants are those who authorized to do transactions on behalf of you, such as stock brokers).

B). Once they confirm your CDS account number, you can contact your broker through the Phone, Fax, Personal visit or from the Internet to trade in the secondary market.

C). Conditions - The buyer must make payment for shares bought by the 3rd trading day after the purchase (T+3). The seller will receive payment for shares sold by the 3rd trading day after the sale (T+3)

6. Trading sessions - The Exchange is open for continuous trading from Monday to Friday from 9.30 a.m. to 2.30 p.m. “Pre-Open” session is from 9-9.30am where investors can order to buy and sell, but can amend those orders before 9.30am.

7 Trading Systems

A). Automated Trading System (ATS): is a real time system that provides secondary trading of equities. It supports high-speed transactions, price-time matching for orders, detailing on price history, online reporting, corporate announcements, information on holding stocks and pending orders.

B). DEX (Debt Securities Trading System): designed to facilitate the trading of corporate and government debt securities.

Source: http://www.cse.lk/welcome.htm

GSM Protocol Architecture - Part 3: Signaling Plane

In GSM network architecture, signaling plane (control plane) is defined for transmitting, and controlling of signals between network elements. Few essential protocol entities can be identified in this signaling plane architecture.

Connection Elements

Signaling plane consists of three distinguished connection elements.

1. Radio-interface connection element – between MS & BTS

2. BSS-interface connection element – between BTS & BSC

3. A-interface connection element – between BSC & MSC

Let’s try to focus on the protocols by relating to the much familiar ISO network model.

Layer 1: Physical Layer

In simple terms this is where the signal meets the air interface e. Thus the physical layer protocols implement the logical signaling channels. Signaling messages will be transport over Abis and A interaces on a digital line.

Layer 2: Data-link Layer – LAPDm

LAPDm (Link Access Procedure in Dm channels) is the protocol defined at this layer. LAPDm is dedicated to transparent transport of messages between protocol entities of layer 3 through services such as information framing, peer-to-peer transmission of data in defined frames, recognition of frame formats and establish, maintain and terminate of one or more data links on signaling channels.

Layer 3: Networking Layer

Protocols in layer 3 are used for communication of network resources, code format, call management etc. The services offered by layer 3 protocols can be categorized under three sub layers.

1. Radio Resource Management (RR) – Performs the administration tasks related to frequencies and channels

2. Mobility Management (MM) – Dedicated to handle tasks resulting from mobility such as TMSI assignment, location related activities, identification, authentication and detaching IMSI.

3. Connection Management (CM) – Consists of three sub-services

• Call Control (CC) – Set-up, maintenance and take down calls
• Supplementary Services – To utilize the services of USSD
• SMS – Point-to-point short message transmission