... DataLinkLayer Protocols- The Frame
31
• Remember that although there are many different DataLinklayerprotocols that describe
Data Linklayer frames, each frame ... logical signal paths are defined by DataLinklayer
protocols.
• The DataLinklayer "sees" the logical topology of a network when
24
• The DataLinklayer "sees" the logical ... chapter, you will be able to:
• Explain the role of DataLinklayerprotocols in data transmission.
• Describe how the DataLinklayer prepares data for transmission on
network media.
• Describe...
...
+ HF – (thoại tương tự)
+ VHF Data link: VDL Mode2 – (dữ liệu), VDL mode3 - (thoại và dữ liệu), và
VDL mode4 - (dữ liệu).
+ SSR Mode S - (dữ liệu)
+ HF Datalink – (dữ liệu).
Các dịch vụ thông ... trên vùng lãnh thổ Việt Nam.
Luận văn “ ỨNG DỤNG CỦA VHF DATALINK MODE 4 TRONG MÔI TRƯỜNG CNS/
ATM ” nghiên cứu công nghệ kỹ thuật VHF DataLink Mode 4, một liên kết dữ liệu số
sử dụng sóng VHF ... phân lớp điều khiển truy nhập MAC ( Medium
Access Control ), Dịch vụ liên kết dữ liệu DLS ( DataLink service ) và thực thể quản lý
liên kết ( LME ). Lớp liên kết dữ liệu VDL cung cấp sự truyền...
...
CHAPTER 8 ■ DATA ACCESS LAYER
174
private void DisconnectFromDatabase()
{
if (_databaseConnection.State != ConnectionState.Open)
{
_databaseConnection.Close();
}
}
private IDataReader ... CreateUserFromReader(IDataReader dataReader)
{
int id = dataReader.GetInt32(0);
string name = dataReader.GetString(1);
string emailAddress = dataReader.GetString(2);
string password = dataReader.GetString(2); ... the project, only the parts of the database that are in use by the object model should have
been generated.
CHAPTER 8 ■ DATA ACCESS LAYER
164
DATABASE KEYS
Database tables should always have...
... modules that focus on the data access layer
(DAL). In Module 8, “The Nontransactional Data Access Layer, ” you learned
about data retrieval. In this module, you will learn about data manipulation. ... same data
access technologies as that of the nontransactional DAL. The following data
access technologies were covered in Module 8, “The Nontransactional Data
Access Layer :
!
Microsoft Data ...
DAL: Module 8, “The Nontransactional Data Access Layer and Module 9,
“The Transactional Data Access Layer. ” The DAL is an application’s means of
access to data services.
After completing this...
... Nontransactional Data Access Layer 15
Data Shaping Service
!
Relation-based Hierarchical Rowsets
!
Group-based Hierarchies
!
Using Data Shaping
!
Sample Definition
OLE DB provides a Data Shaping ... is any component that owns data. It exposes its data in a
tabular format, regardless of the format in which it stores data. Examples of
data providers are relational database management systems ... Nontransactional Data Access Layer
#
##
#
Introduction to the Data Access Layer
!
The Business Problem
!
Splitting the DAL
The DAL buffers the entire system from the underlying data services....
... trường hợp về sự cố mạng có thể do phần cứng hay phần mềm:
Phần cứng (Lớp Physical, Data Link) : Đèn liên kết (Link ) của card mạng không
sáng
Kiểm tra đầu nối card mạng và đầu cáp nối trên HUB/SWITCH
...
... same data
access technologies as that of the nontransactional DAL. The following data
access technologies were covered in Module 8, “The Nontransactional Data
Access Layer :
!
Microsoft Data ... DAL.
Module 9: The Transactional Data Access Layer 3
The Business Problem
DAL
Connected Business
Logic Layer
Disconnected Business
Logic Layer
Facade Layer
Web Services Facade Business ... data services layer. The transactional DAL can return to the
business logic layer either success or failure. If the transaction also involved
retrieving data as a result of updates to the data, ...
...
Recipe 1.13 Using the DataLink Properties Dialog Box
Problem
You want to display the DataLink Properties dialog
b
ox from an application so that users
can create their own database connections ... Reference
Dialog.
The sample code contains a single event handler:
Data Link Dialog Button.Click
Creates and displays a DataLink Properties dialog box using the Microsoft OLE
DB Service Component ... shown in Example 1-10
.
Example 1-10. File: DataLinkDialogForm.cs
// Namespaces, variables, and constants
using System;
// . . .
private void dataLinkDialogButton_Click(object sender, System.EventArgs...
... was to another vendor in San Francisco. TEHO takes advantage of the
WAN link, but then the call goes through a San Francisco gateway incurring only a local San Francisco toll
charge. It is very ... hotel; database lookups for cus-
tomers; and information brought to the IP phone, such as weather, stock quotes, airport delays; etc.
Cisco VoIP Products
Cisco CallManager (CCM)
In 1998, Cisco ... Knowledge courses:
CVOICE (Cisco Voice over IP)
QOS (Implementing Cisco Quality of Service)
CIPT part 1 and 2 (Cisco IP Telephony)
Unity Administration and Engineering
UCCXD (Cisco Contact Center Express...