KT’s Vision: GiGAtopia Source: KT What? Chairman Chang-gyu Hwang of KT (with sales of KRW 23.8 trillion in 2013), at a press conference held at KT Olleh Square in Gwanghwamun, Seoul on May 20, announced that "KT will open up a new age of GiGAtopia by investing KRW 4.5 trillion (USD 4.4 billion) in GiGA FTTH, GiGA Path (heterogeneous networks convergence technology that combines...

As mobile communication technology has evolved dramatically, from LTE (10 MHz) to LTE-A (10+10 MHz), and then to wideband LTE (20 MHz), South Korea's mobile market is hotter than ever with its big 3 operators competing fiercely in speed and quality (see Netmanias Report, LTE in Korea UPDATE - May 1, 2014). Operators can offer different maximum speeds depending on how wide frequency bandwidt...

HFR is probably most known as a vendor of wired/wireless network equipment like Mobile fronthaul, Carrier Ethernet, FTTx, etc. Today, we are going to hear from Dr. J.H. Lee (jongheonlee@hfrnet.com), CTO of HFR about one of its most popular solutions, flexiHaulTM, a mobile optical access solution. 1. Welcome! Thank you for being with us. Can you tell us a little bit about HFR first?...

1. Traditional RAN Architecture and Issues 1.1 Issue No. 1: Degraded service quality and network performance due to inter-cell interference 1.2 Issue No. 2: Increased costs of building and operating cell sites 2. Degradation of service quality and network performance due to inter-cell interference: Prevented by reducing X2 distance 3. Costs of building and operating cell sites: Reduced...

In C-RAN (Centralized/Cloud RAN), the more RRHs are covered by one CO (BBU hostelling site), i) the fewer COs are required, and ii) the more BBUs can be centralized at one CO. This allows for the most efficient utilization of BBU resources, thereby significantly reducing CAPEX/OPEX. For this reason, the maximum separation distance between RRH and BBU should be secured. This distance is cons...

Our question in this post is: Why does the CPRI link between BBU (at CO) and RRH (at Cell Site) in C-RAN require a ultra high Gbps bandwidth? Before you read this post, we advise you to read our previous post, "CPRI (1): Emergence of C-RAN and CPRI overview". The CPRI link capacities required between BBU and RRH in the C-RAN architecture are as follows: Table 1. CPRI data rates...

Emergence of C-RAN (Separation of Baseband and Radio, and Baseband Centralization) Today, global LTE operators are competing with one another more fiercely than ever, under the pressure to provide better service quality and higher speed. Conventional Internet traffic has been increasing steadily. What's more, mobile traffic resulting from OTT video services, such as YouTube, Mobile IPT...

In the last two posts (Part 1, Part 2), we learned about LTE QoS. Now, we will show you an example of controlling P2P traffic using the LTE QoS in the LTE network. Let's say there is a network operator named "NMC Telecom", and it offers a service plan with the following features: No bandwidth limitation for Internet usage Data rate limitation (512 Kbps for download, and 128 Kbps fo...

We will look a little bit further into LTE QoS that we discussed last time, and learn what QoS parameters are for. There are two types of EPS bearers: default and dedicated. In the LTE network, the EPS bearer QoS is controlled using the following LTE QoS parameters: ▶ Resource Type: GBR or Non-GBR ▶ QoS Parameters QCI ARP GBR MBR APN-AMBR UE-AMBR Every EPS bearer must...

We will talk about LTE QoS this time. QoS functions provided by any network, whether wired or wireless, are all based on standards (IETF RFC, IEEE 802, 3GPP TS, etc.). They may work differently using different standards depending on whether the network is wired (Ethernet/IP/MPLS) or wireless (LTE/WiBro/Wi-Fi). But, basically what the QoS is about is that traffic quality is guaranteed (i) if...

Today, we will find more about LTE GTP tunnels that we have discussed previously. In the Figure below, GTP tunnels are established in the link from the eNB to the S-GW and from the S-GW to the P-GW. Downlink (DL): From PDN (Internet) to UE [1] A packet (Source IP=www.google.com, Destination IP=UE) is sent from the Internet to the P-GW. [2] The P-GW compares the five tuples of...

SK Telecom, the Korean No. 1 telecom operator, launched Btv Mobile service (in SD/HD) offering a variety of live broadcasting and VoD contents for mobile devices in around July 2012. And a year later in July 2013, boosted by the commercialization of LTE-A, it began a "Full HD" streaming service with drastically enhanced video quality. The following is the press release by SK Telecom about its n...

Today, we will talk about GTP tunnels used in the LTE network. As seen in Figure (a) below, IP packets sent by an LTE device (UE) are delivered from an eNB to a P-GW through GTP tunnels. What it means is that "all IP packets that a UE sends are always delivered through an eNB to a P-GW regardless of their specified destination IP addresses (i.e., even though their destination IP addresses a...

This time we will give you a brief overview of an LTE Tracking Area (TA) and Tracking Area Update (TAU). While an LTE device (UE) is in active state (i.e. while communicating, or while in EMM-Registered/ECM-Connected/RRC-Connected state in LTE terms), its location is known by the LTE network at cell level (i.e. on a cell granularity), e.g. in cell2 in eNB1. However, while the UE is in idle...

On June 10, 2013, LG U+ launched U+ HDTV multi-channel service (U+ tv G 4 Channel Service) that enables users to watch 4 channels at the same time through home STB. Later in July, it introduced the same multi-channel service in a mobile version based on LTE-A. In this post, we will analyze the U+ HDTV streaming on mobile devices that support LTE-A. U+ HDTV service offers two viewing experi...

Today's topic is IMSI (International Mobile Subscriber Identity) and GUTI (Globally Unique Temporary Identifier). These two are parameters (identifiers) used in identifying UEs in LTE networks. What is IMSI? IMSI is a unique ID that globally identifies a mobile subscriber. It is composed of two parts, PLMN ID and MSIN, as shown in Figure below. A PLMN ID is an ID that globally identi...

All wireless telecommunication networks (e.g. Wi-Fi, WiBro and LTE provide “user authentication” and “security over radio link (integrity check (protection/verification) and ciphering (or encryption))” features. User authentication is required for network operators to ensure that only those who subscribe to them (i.e. paid subscribers) can access their networks. In wir...

Obviously, the hottest issue in mobile communication today is LTE. All three top telecommunication operators in Korea are trying hard to promote their brands, each containing the technical term "LTE" somewhere, for greater exposure of the brands to the public. So, we will briefly go over what network elements make the LTE network today. The Figure below is an illustration of an LTE Network R...