The rapid growth of global routing tables has raised concerns among many Internet Service Providers. The most immediate concern regarding routing scalability is the size of the Forwarding Information Base (FIB), which seems to be growing at a faster pace than router hardware can support. This paper focuses on one potential solution to this problem -FIB aggregation, i.e., aggregating FIB entries without affecting the forwarding paths taken by data traffic. Compared with alternative solutions to the routing scalability problem, FIB aggregation is particularly appealing because it is a purely local software optimization limited within a router, requiring no changes to routing protocols or router hardware. To understand the feasibility of using FIB aggregation to extend router lifetime, we present several FIB aggregation algorithms and evaluate their performance using routing tables and updates from tens of networks. We find that FIB aggregation can reduce the FIB table size by as much as 70% with small computational overhead. We also show that the computational overhead can be controlled through various mechanisms.
A new electrochemical biosensing method was developed based on the immobilization of DNA probes on photolithographic gold film electrodes by self‐assembled monolayer technique. The complementary sequence was hybridized to the modified electrode and the hybridization reaction was carried out at 37 °C for 1 h. Avidin‐akaline phosphatase was coupled to the hybrid through avidin‐biotin complex and hydrolyzed to produce an electroactive α‐naphthol, which could be detected by different pulse voltammetry (DPV). Numerous factors including the concentration of the substrate and incubation time are optimized to maximize the sensitivity and speed in the assay time. The sensors were employed to detect PCR products relative to the hepatitis B plasmid. The method has a linear calibration range of 1.5 nmol/L–50 nmol/L and the detection limit is 30 fmol.
Abstract-The global routing table size has been increasing rapidly, outpacing the upgrade cycle of router hardware. Recently aggregating the Forwarding Information Base (FIB) emerges as a promising solution since it reduces FIB size significantly in the short term and it is compatible with any long-term architectural solutions. Because FIB entries change dynamically with routing updates, an important component of any FIB aggregation scheme is to handle routing updates efficiently while shrinking FIB size as much as possible. In this paper, we first propose two incremental FIB aggregation algorithms based on the ORTC scheme. We then quantify the tradeoffs of the proposed algorithms, which will help operators choose the algorithms best suited for their networks.
During the past decade, numerous investigations have demonstrated that the rate at which amide hydrogens located at peptide linkages undergo isotopic exchange is a sensitive probe of the high order structure and dynamics of proteins. The present investigation demonstrates that microbore high-performance liquid chromatography (HPLC) continuous-flow fast-atom bombardment mass spectrometry (FABMS) can be used to accurately quantify deuterium located at peptide linkages in short segments of large proteins. This result is important because it demonstrates the feasibility of using mass spectrometry as a tool for studying the high order structure and dynamics of large proteins. Following a period of deuterium exchange-in, a protein was placed into slow-exchange conditions and fragmented into peptides with pepsin. The digest was analyzed by continuous-flow HPLC FABMS to determine the molecular weights of the peptides, from which the number of deuterons located at the peptide linkages could be deduced. The HPLC step was used both to fractionate the peptides according to their hydrophobicities and to remove through back-exchange all deuterium except that located at peptide amide linkages. This approach has been applied to α-crystallin, a lens protein composed of two gene products with monomer molecular weights of 20 kDa and an aggregate molecular weight approaching 1000 kDa. Results from this study show that some of the peptide amide hydrogens in αA-crystallin exchange very rapidly (k> 10 h(-1)) while others exchange very slowly (k < 10(-3) h(-1)). The ability not only to detect that a conformational change has occurred, but also to identify the specific regions within the protein where the change occurred, was demonstrated by measuring changes in the exchange rates within these regions as the deuterium exchange-in temperature was increased from 10 to 80 ° C.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.