I get wireless, 3G and 2G network connection via my iPhone. I tested the network speed of a wireless, 3G and 2G network possible from my iPhone using the App from OFCA. Wifi of sMobileNet network in HKUST: 25604 kbps: 3G network from a carrier in Hong Kong: 2776 kbps: 2G network from a carrier
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Tag: Network
How to Change Hostname of Fedora Linux
Posted onDifferent Linux distros have different method to set the hostname. On Fedora Linux, it is quite simple. On newer Fedora releases At least from Fedora 19 (sorry, no sure the exact earliest version): You need to edit the file /etc/hostname which just contains the hostname. On older Fedora releases Sorry, I do not know the
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Installing ns-2 and ns-3 on Fedora Linux
Posted onns is a discrete-event network simulator targeted primarily for research and educational use. There are two version of ns, ns-2 and ns-3, which are quite different with each other in the implementation and method to use them. In this post, we introduce how to install ns-2 and ns-3 on Fedora Linux 15. Install ns-2.34 on
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How to Upgrade Fedora to Newer Version with Yum
Posted onThe latest tools for upgrading Fedora is FedUp, please check How to upgrade Fedora 19 to Fedora 20 through the network. Please consider PreUpgrade for upgrading Fedora. This is the recommended method. This post makes a list of actions should be done to upgrade Fedora using yum. Please note that this is for experienced users
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A Tutorial on Ns-2
Posted onThis is a tutorial on ns-2 which gives a overview of ns-2 and introduces how to define a simple topology and the network flow. This tutorial is based on the slides for Lab session of COMP 4622 at HKUST in the fall semester of 2011. The slides of tutorial on ns-2 can be download from
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How to disable IPv6 on Linux (Old Version Kernels)
Posted onUpdate: this only works on older Linux kernels (e.g. Fedora 12). For newer kernels, please see How to disabling IPv6 on Linux IPv6 is enabled by default on most Linux distros. However, IPv4 is still the mostly used network and IPv6 is not used in many environment. This post introduces how to disable IPv6 support on
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Setting Up Ubuntu DomU on Xen: Ubuntu 10.10 on Fedora Xen Dom0
Posted onSetting up Ubuntu 10.10 DomU on top of Fedora Xen Dom0 is introduced in this post. The process of setting up Ubuntu 10.10 DomU is the same as Setting Up Stable Xen DomU with Fedora: Unmodified Fedora 12 on top of Xenified Fedora 12 Dom0 with Xen 4.0 This post only show the difference which
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Setting Up VPN-like Network Between Several Clusters Using iptables
Posted onIt is common to connect servers with only internal IPs from several clusters. VPN is a common technique for this. With iptables, we can implement many functions of VPN with possibly higher performance. The slides here give a brief introduction to how to set up a VPN-like network between 2 clusters which connect to each
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Duplicating LVM Backed Xen DomU
Posted onLVM’s snapshot feature enables us to duplicate an LVM backed Xen DomU in seconds rather than minutes. We no longer need to copy the entire file system image like backing up file backed Xen DomU. We just need to make a snapshot of the current Xen DomU in seconds. When there are changes to the
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Introduction to Xen Source Code Structure
Posted onThe Xen hypervisor is a powerful virtualization solution that provides virtualization capabilities for x86, x86-64, and ARM architectures. The source code structure of Xen is organized into several directories, each of which contains a specific set of files. The backend and frontend drivers are an important part of the Xen hypervisor, and they provide a
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Duplicating and Backing Up LVM Backed Xen DomU from a Remote Server
Posted onLVM’s snapshot feature enables us to duplicate an LVM backed Xen DomU in seconds inside of the same volume group. When we want to duplicate LVM backed Xen DomU from a remote server, we need to make use of LVM’s snapshot function and tools like scp and dd. Backing up the DomU is only part
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Linux Cluster Solutions
Posted onSolutions to Linux cluster construction and management such as unified account management, NFS home directory, network configurations are summarised in this post. The post is keeping updating while new solutions is added to this site. ===Account and storage management=== [[unified-linux-login-and-home-directory-using-openldap-and-nfsautomount|Unified Linux Login and Home Directory Using OpenLDAP and NFS/automount]] [[backup-linux-home-directory-using-rsync|Backup Linux Home Directory Using rsync]]
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Setting up Stable Xen Dom0 with Fedora: Xen 3.4.3 with Xenified Linux Kernel 2.6.32.13 in Fedora 12
Posted onThis is the latest stable and recommended stable Xen Dom0 solution on Fedora 12. No serious bug found till now and we will fix the bugs by ourselves if some appears. It also works on Fedora 14 as well. It should not be hard to use this solution on other versions of Fedora or other
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How to Create Fedora Live USB Media
Posted onHow to create a Fedora live USB media is introduced in this post. We can boot to Fedora operating system environment through a live USB system in the USB flash media on a USB-bootable computer without writing the computer’s hard disk. We can also install Fedora operating system from the live system environment. Remember to
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Problems during Installing Xen Dom0 in Fedora
Posted onHere is a list of problem that may occur during installing and configuring Xen Dom0 in Fedora. It is found originally in Fedora systems, but the tips in this post should also be helpful for installing Xen Dom0 on other platforms. BIOS configuration If xen stops at: “I/O virtualization disabled.” We may need to enable
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Finding out Linux Network Configuration Information
Posted onThere is various network configuration information in Linux and lots tools can be used to find out those configuration information. Finding out these network information in Fedora Linux as the example will be introduced. IP address, MAC address and netmask ifconfig will print out all the network interfaces and their information including the IP address
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Setting Up Xen DomU on Fedora Linux (Fedora 12)
Posted onCreating file-backed virtual block device (VBD) for Xen virtual machines and installing Fedora 12 in Xen DomU via internet will be introduced. Note that this tutorial is based on a pretty old OS (Fedora 12). But the method here is still valid while some minor details may need to be changed for latest Xen and
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Changing MAC Address in Linux aka. MAC Spoofing
Posted onMAC stands for Media Access Control which is a six byte number, usually expressed as a twelve digit hexadecimal number. IPs in LAN are translated to MAC address by the ARP (Address Resolution Protocol) protocol. For some reasons such as keeping the true MAC address from being logged, accessing to the network which bounds IPs
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Linux Port Forwarding Using iptables
Posted onLinux port forwarding is simple to do with iptables which may probably already being used as the firewall or part of the setting up a Linux gateway. In the Linux kernel, port forwarding is achieved by packet filter rules in iptables. Port forwarding Port forwarding also called “port mapping” commonly refers to the network address
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Speeding Up Firefox in Linux
Posted onFirefox can be much faster on Linux! Let’s speed up Firefox on Linux system. Part 1 and 2 only config firefox, so it can also be used on other platform such as Windows. 1. Pipe-lining network connection Most of us use a broad band width network, then why not pip line the connection from Firefox?
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