IOSR Journal of Computer Engineering (IOSRJCE)
... computers without using wires. WLAN utilizes spread-spectrum or OFDM (802.11a) modulation technology based on radio waves to enable communication between devices in a limited area, also known as the basic service set. This gives users the mobility to move around within a broad coverage area and stil ...
... computers without using wires. WLAN utilizes spread-spectrum or OFDM (802.11a) modulation technology based on radio waves to enable communication between devices in a limited area, also known as the basic service set. This gives users the mobility to move around within a broad coverage area and stil ...
PowerPoint
... users often wish to perform more than one activity at a time and uniprogramming does not allow this. z Uniprogrammed systems put in things like memory-resident programs that invoked asynchronously. One key problem with DOS is that there is no memory protection - one program may write the memory of a ...
... users often wish to perform more than one activity at a time and uniprogramming does not allow this. z Uniprogrammed systems put in things like memory-resident programs that invoked asynchronously. One key problem with DOS is that there is no memory protection - one program may write the memory of a ...
Threads
... make blocking system calls while also achieving parallelism. Kernel-supported threads (Mach and OS/2). User-level threads; supported above the kernel, via a set of library ...
... make blocking system calls while also achieving parallelism. Kernel-supported threads (Mach and OS/2). User-level threads; supported above the kernel, via a set of library ...
Chord - Networked Systems Laboratory
... • Routing table (finger table) - (at most) m entries. The ith entry of node n contains the pointer to the first node that succeeds n by at least 2(i-1) on the key space, 1 i m. ...
... • Routing table (finger table) - (at most) m entries. The ith entry of node n contains the pointer to the first node that succeeds n by at least 2(i-1) on the key space, 1 i m. ...
Simulation-Assisted Routing Protocol Design (SARPD)
... Finally, the design assumes a time-varying topology such that sometimes a given radio is a single hop away and sometimes it is more than one hop away. ...
... Finally, the design assumes a time-varying topology such that sometimes a given radio is a single hop away and sometimes it is more than one hop away. ...
Unmodified Device Driver Reuse and Improved System Dependability via Virtual Machines
... level. The client interfaces with the driver via a translation module added to the device driver’s OS. This module behaves as a server in a client-server model. It maps client requests into sequences of DD/OS primitives for accessing the device, and converts completed requests into appropriate respo ...
... level. The client interfaces with the driver via a translation module added to the device driver’s OS. This module behaves as a server in a client-server model. It maps client requests into sequences of DD/OS primitives for accessing the device, and converts completed requests into appropriate respo ...
as a PDF
... One program shouldn’t steal or alter another’s data Stop or clean up a program when it does something wrong ...
... One program shouldn’t steal or alter another’s data Stop or clean up a program when it does something wrong ...
Routing
... When a router is initialized, it determines the link cost on each of its network interfaces The router then advertises this set of link costs to all other routers in the internet topology, not just neighboring routers From then on, the router monitors its link costs Whenever there is a significant c ...
... When a router is initialized, it determines the link cost on each of its network interfaces The router then advertises this set of link costs to all other routers in the internet topology, not just neighboring routers From then on, the router monitors its link costs Whenever there is a significant c ...
3. Processes
... Although two processes may be associated with the same program, they are nevertheless considered two separate execution sequences. For instance, several users may be running different copies of the mail program, or the same user may invoke many copies of the editor program. Each of these is a separa ...
... Although two processes may be associated with the same program, they are nevertheless considered two separate execution sequences. For instance, several users may be running different copies of the mail program, or the same user may invoke many copies of the editor program. Each of these is a separa ...
Compensation of Asymmetrical Latency for Ethernet Clock
... between the link partners is done by an out-of-band communication scheme, orthogonal to Ethernet, creating two logical links. One of them is used for the normal user traffic and is driven by a standard PHY. The other logical link is created by a custom IC dealing with synchronization only, while usi ...
... between the link partners is done by an out-of-band communication scheme, orthogonal to Ethernet, creating two logical links. One of them is used for the normal user traffic and is driven by a standard PHY. The other logical link is created by a custom IC dealing with synchronization only, while usi ...
Examples
... Synchronized network Base station is in the middle of network All nodes are homogeneous and energy constrained Nodes are distributed according a homogeneous spatial Poisson process of intensity All sensors transmit at the same power level and have the same communication radius r Each sensor uses 1 u ...
... Synchronized network Base station is in the middle of network All nodes are homogeneous and energy constrained Nodes are distributed according a homogeneous spatial Poisson process of intensity All sensors transmit at the same power level and have the same communication radius r Each sensor uses 1 u ...
How the Sybil Attack can be used in wireless sensor
... – The time complexity to generate a usable Sybil node ID given a set of compromised nodes could be expressed in terms of the probability p that a random identity is a usable Sybil identity. – So, the expected number of times an attacker has to try to find a usable Sybil identity is 1/p. ...
... – The time complexity to generate a usable Sybil node ID given a set of compromised nodes could be expressed in terms of the probability p that a random identity is a usable Sybil identity. – So, the expected number of times an attacker has to try to find a usable Sybil identity is 1/p. ...
Distributed Computation of Reduced Multicast Trees
... new member. It creates a new tree branch from the duplication point to the new member. It notifies the new member that it is being inserted as a tree leaf, and of the identity (Neighbour) of its father in the tree. PRUNE Neighbour. The pruning message is symmetrical to the previous message. A leaf n ...
... new member. It creates a new tree branch from the duplication point to the new member. It notifies the new member that it is being inserted as a tree leaf, and of the identity (Neighbour) of its father in the tree. PRUNE Neighbour. The pruning message is symmetrical to the previous message. A leaf n ...
document
... Hand-held computers typically use a miniature keyboard in combination with a touch screen. Palm-sized computers use a stylus and touch screen exclusively in combination with a handwriting recognition program. The screen of the palm PDA serves as an input as well as an output device. It displays info ...
... Hand-held computers typically use a miniature keyboard in combination with a touch screen. Palm-sized computers use a stylus and touch screen exclusively in combination with a handwriting recognition program. The screen of the palm PDA serves as an input as well as an output device. It displays info ...
Module 7: Process Synchronization
... If graph contains no cycles no deadlock. If graph contains a cycle if only one instance per resource type, then deadlock. if several instances per resource type, possibility of ...
... If graph contains no cycles no deadlock. If graph contains a cycle if only one instance per resource type, then deadlock. if several instances per resource type, possibility of ...
A deterministic worst-case message complexity optimal solution for
... setting. However, these spanning trees are either expensive to maintain or the amount of work in these algorithms is not being considered. However, these spanning trees are potentially expensive to maintain as a high degree cannot be avoided in general (consider, for example, the extreme case of a s ...
... setting. However, these spanning trees are either expensive to maintain or the amount of work in these algorithms is not being considered. However, these spanning trees are potentially expensive to maintain as a high degree cannot be avoided in general (consider, for example, the extreme case of a s ...
4. Process
... A message-based approach: – processes communicate without shared vars Two basic operations: – send(message) – receive(message) ...
... A message-based approach: – processes communicate without shared vars Two basic operations: – send(message) – receive(message) ...
ch13
... attempt to disrupt normal operation via illegal I/O instructions All I/O instructions defined to be privileged I/O must be performed via system calls Memory-mapped and I/O port memory ...
... attempt to disrupt normal operation via illegal I/O instructions All I/O instructions defined to be privileged I/O must be performed via system calls Memory-mapped and I/O port memory ...
Opportunistic Routing in Multi
... We begin with an overview of the protocol and supply details in the subsections below. The ExOR protocol consists of three stages: selecting the forwarding candidates, acknowledging transmissions, and deciding whether to forward a received packet. Throughout this description we assume each node in t ...
... We begin with an overview of the protocol and supply details in the subsections below. The ExOR protocol consists of three stages: selecting the forwarding candidates, acknowledging transmissions, and deciding whether to forward a received packet. Throughout this description we assume each node in t ...
.pdf
... to more traditional computing environments like clusters or super computers, the network characteristics between grid sites are both very heterogeneous and dynamically changing. Therefore, communication libraries need to take this heterogeneity into account to maintain efficiency in a world-wide env ...
... to more traditional computing environments like clusters or super computers, the network characteristics between grid sites are both very heterogeneous and dynamically changing. Therefore, communication libraries need to take this heterogeneity into account to maintain efficiency in a world-wide env ...
AZ26337342
... nodes. There are many protocols that have been developed to aid in routing in these types of networks. Each of these protocols is designed with some certain mobility scenarios in mind. To achieve effective routing in a given scenario, the right protocol must be chosen. Choosing the right protocol in ...
... nodes. There are many protocols that have been developed to aid in routing in these types of networks. Each of these protocols is designed with some certain mobility scenarios in mind. To achieve effective routing in a given scenario, the right protocol must be chosen. Choosing the right protocol in ...
Distributed operating system
A distributed operating system is a software over a collection of independent, networked, communicating, and physically separate computational nodes. Each individual node holds a specific software subset of the global aggregate operating system. Each subset is a composite of two distinct service provisioners. The first is a ubiquitous minimal kernel, or microkernel, that directly controls that node’s hardware. Second is a higher-level collection of system management components that coordinate the node's individual and collaborative activities. These components abstract microkernel functions and support user applications.The microkernel and the management components collection work together. They support the system’s goal of integrating multiple resources and processing functionality into an efficient and stable system. This seamless integration of individual nodes into a global system is referred to as transparency, or single system image; describing the illusion provided to users of the global system’s appearance as a single computational entity.