Increased user concern over security and privacy on the Internet has led to widespread adoption of HTTPS, the secure version of HTTP. HTTPS authenticates the communicating end points and provides confidentiality for the ensuing communication. However, as with any security solution, it does not come for free. HTTPS may introduce overhead in terms of infrastructure costs, communication latency, data usage, and energy consumption. Moreover, given the opaqueness of the encrypted communication, any in-network value added services requiring visibility into application layer content, such as caches and virus scanners, become ineffective.This paper attempts to shed some light on these costs. First, taking advantage of datasets collected from large ISPs, we examine the accelerating adoption of HTTPS over the last three years. Second, we quantify the direct and indirect costs of this evolution. Our results show that, indeed, security does not come for free. This work thus aims to stimulate discussion on technologies that can mitigate the costs of HTTPS while still protecting the user's privacy.

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Live video delivery is expected to reach a peak of 50 Tbps this year [7]. This surging popularity is fundamentally changing the Internet video delivery landscape. CDNs must meet users' demands for fast join times, high bitrates, and low buffering ratios, while minimizing their own cost of delivery and responding to issues in real-time. Wide-area latency, loss, and failures, as well as varied workloads ("mega-events" to long-tail), make meeting these demands challenging.An analysis of video sessions [32] concluded that a centralized controller could improve user experience, but CDN systems have shied away from such designs due to the difficulty of quickly handling failures [29], a requirement of both operators and users. We introduce VDN, a practical approach to a video delivery network that uses a centralized algorithm for live video optimization. VDN provides CDN operators with real-time, fine-grained control. It does this in spite of challenges resulting from the wide-area (e.g., state inconsistency, partitions, failures) by using a hybrid centralized+distributed control plane, increasing average bitrate by 1.7× and decreasing cost by 2× in different scenarios.

Though most would agree that accountability and privacy are both valuable, today's Internet provides little support for either. Previous efforts have explored ways to offer stronger guarantees for one of the two, typically at the expense of the other; indeed, at first glance accountability and privacy appear mutually exclusive. At the center of the tussle is the source address: in an accountable Internet, source addresses undeniably link packets and senders so hosts can be punished for bad behavior. In a privacy-preserving Internet, source addresses are hidden as much as possible.In this paper, we argue that a balance is possible. We introduce the Accountable and Private Internet Protocol (APIP), which splits source addresses into two separate fields -an accountability address and a return address -and introduces independent mechanisms for managing each. Accountability addresses, rather than pointing to hosts, point to accountability delegates, which agree to vouch for packets on their clients' behalves, taking appropriate action when misbehavior is reported. With accountability handled by delegates, senders are now free to mask their return addresses; we discuss a few techniques for doing so.

Though most would agree that accountability and privacy are both valuable, today's Internet provides little support for either. Previous efforts have explored ways to offer stronger guarantees for one of the two, typically at the expense of the other; indeed, at first glance accountability and privacy appear mutually exclusive. At the center of the tussle is the source address: in an accountable Internet, source addresses undeniably link packets and senders so hosts can be punished for bad behavior. In a privacy-preserving Internet, source addresses are hidden as much as possible.In this paper, we argue that a balance is possible. We introduce the Accountable and Private Internet Protocol (APIP), which splits source addresses into two separate fields -an accountability address and a return address -and introduces independent mechanisms for managing each. Accountability addresses, rather than pointing to hosts, point to accountability delegates, which agree to vouch for packets on their clients' behalves, taking appropriate action when misbehavior is reported. With accountability handled by delegates, senders are now free to mask their return addresses; we discuss a few techniques for doing so.

The present study (N = 30 female rats, 11 male rats) was conducted to determine the effects of prenatal stress on rat offsprings' learning ability. Pregnant mothers were stressed by exposure to an SD (light) which had been paired with shock. A second group of pregnant rats was handled an equivalent amount of time, and a third group received no treatment. The offspring of the three groups were tested on several learning tasks and the handled and stressed groups were found to be inferior to the control group on four of six learning measures.

A B S T R A C TIt is known that there are 100 A-wide circular structures associated with the erythrocyte membrane in immune lysis. To determine whether these structures were functional holes extending through the membrane, freeze-etch electron microscopy was carried out. Sheep erythrocytcs incubatcd with either rabbit complement or rabbit antibody (anti-sheep erythrocyte antibody) did not hemolyzc and did not reveal any abnormalitics in freezectch or negative-stain clcctron microscopy. Erythrocytes incubated with both complement and antibody revealed rings on the extracellular surface (etch face) of the cell membrane. o Allowing for the 30 A-thick Pt/C replica, the dimensions of the surface rings were similar to those seen by negative staining. The ring's central depression was level with the plane of the membrane; some rings were closed circles, othcrs were crescent shaped. The cleavage face of the cxtraccllular leaflet revealed globule aggregates, each aggregate appearing to be composed of about four fused globules. The cleavage face of the cytoplasmic leaflet was normal. When immune lysis was carried out in the presence of ferritin, fcrritin was subsequently detected in all lysed erythrocytes. If ferritin was added after immune lysis was complete, only 15 % of the cells were pcrmcatcd by fcrritin, indicating that transien[ openings exist in the cell membrane during immune lysis. No abnormal structures were detected when C6-deficicnt rabbit serum was used as a source of complement. It is concluded that antibody and complement produce surface rings, prelytic leakage of K +, colloid osmotic swelling, membrane disruption, and membrane resealing; the surface rings persist after these events.

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